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X-linked chondrodysplasia punctata 2 is a disorder characterized by bone, skin, and eye abnormalities. It occurs almost exclusively in females. Although the signs and symptoms of this condition vary widely, almost all affected individuals have chondrodysplasia punctata, an abnormality that appears on x-rays as spots (stippling) near the ends of bones and in cartilage. In this form of chondrodysplasia punctata, the stippling typically affects the long bones in the arms and legs, the ribs, the spinal bones (vertebrae), and the cartilage that makes up the windpipe (trachea). The stippling is apparent in infancy but disappears in early childhood. Other skeletal abnormalities seen in people with X-linked chondrodysplasia punctata 2 include shortening of the bones in the upper arms and thighs (rhizomelia) that is often different on the right and left sides, and progressive abnormal curvature of the spine (kyphoscoliosis). As a result of these abnormalities, people with this condition tend to have short stature. Infants with X-linked chondrodysplasia punctata 2 are born with dry, scaly patches of skin (ichthyosis) in a linear or spiral (whorled) pattern. The scaly patches fade over time, leaving abnormally colored blotches of skin without hair (follicular atrophoderma). Most affected individuals also have sparse, coarse hair on their scalps. Most people with X-linked chondrodysplasia punctata 2 have clouding of the lens of the eye (cataracts) from birth or early childhood. Other eye abnormalities that have been associated with this disorder include unusually small eyes (microphthalmia) and small corneas (microcornea). The cornea is the clear front surface of the eye. These eye abnormalities can impair vision. In affected females, X-linked chondrodysplasia punctata 2 is typically associated with normal intelligence and a normal lifespan. However, a much more severe form of the condition has been reported in a small number of males. Affected males have some of the same features as affected females, as well as weak muscle tone (hypotonia), changes in the structure of the brain, moderately to profoundly delayed development, seizures, distinctive facial features, and other birth defects. The health problems associated with X-linked chondrodysplasia punctata 2 are often life-threatening in males. X-linked chondrodysplasia punctata 2 has been estimated to affect fewer than 1 in 400,000 newborns. However, the disorder may actually be more common than this estimate because it is likely underdiagnosed, particularly in females with mild signs and symptoms. More than 95 percent of cases of X-linked chondrodysplasia punctata 2 occur in females. About a dozen males with the condition have been reported in the scientific literature. X-linked chondrodysplasia punctata 2 is caused by mutations in the EBP gene. This gene provides instructions for making an enzyme called 3β-hydroxysteroid-Î8,Î7-isomerase, which is responsible for one of the final steps in the production of cholesterol. Cholesterol is a waxy, fat-like substance that is produced in the body and obtained from foods that come from animals (particularly egg yolks, meat, poultry, fish, and dairy products). Although too much cholesterol is a risk factor for heart disease, this molecule is necessary for normal embryonic development and has important functions both before and after birth. It is a structural component of cell membranes and plays a role in the production of certain hormones and digestive acids. Mutations in the EBP gene reduce the activity of 3β-hydroxysteroid-Î8,Î7-isomerase, preventing cells from producing enough cholesterol. A shortage of this enzyme also allows potentially toxic byproducts of cholesterol production to build up in the body. The combination of low cholesterol levels and an accumulation of other substances likely disrupts the growth and development of many body systems. It is not known, however, how this disturbance in cholesterol production leads to the specific features of X-linked chondrodysplasia punctata 2. This condition is inherited in an X-linked dominant pattern. The gene associated with this condition is located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a mutation in one of the two copies of the EBP gene in each cell is sufficient to cause the disorder. Some cells produce a normal amount of 3β-hydroxysteroid-Î8,Î7-isomerase and other cells produce none. The resulting overall reduction in the amount of this enzyme underlies the signs and symptoms of X-linked chondrodysplasia punctata 2. In males (who have only one X chromosome), a mutation in the EBP gene can result in a total loss of 3β-hydroxysteroid-Î8,Î7-isomerase. A complete lack of this enzyme is usually lethal in the early stages of development, so few males have been born with X-linked chondrodysplasia punctata 2. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to X-linked chondrodysplasia punctata 2 ? | X-linked chondrodysplasia punctata 2 is caused by mutations in the EBP gene. This gene provides instructions for making an enzyme called 3-hydroxysteroid-8,7-isomerase, which is responsible for one of the final steps in the production of cholesterol. Cholesterol is a waxy, fat-like substance that is produced in the body and obtained from foods that come from animals (particularly egg yolks, meat, poultry, fish, and dairy products). Although too much cholesterol is a risk factor for heart disease, this molecule is necessary for normal embryonic development and has important functions both before and after birth. It is a structural component of cell membranes and plays a role in the production of certain hormones and digestive acids. Mutations in the EBP gene reduce the activity of 3-hydroxysteroid-8,7-isomerase, preventing cells from producing enough cholesterol. A shortage of this enzyme also allows potentially toxic byproducts of cholesterol production to build up in the body. The combination of low cholesterol levels and an accumulation of other substances likely disrupts the growth and development of many body systems. It is not known, however, how this disturbance in cholesterol production leads to the specific features of X-linked chondrodysplasia punctata 2. |
X-linked chondrodysplasia punctata 2 is a disorder characterized by bone, skin, and eye abnormalities. It occurs almost exclusively in females. Although the signs and symptoms of this condition vary widely, almost all affected individuals have chondrodysplasia punctata, an abnormality that appears on x-rays as spots (stippling) near the ends of bones and in cartilage. In this form of chondrodysplasia punctata, the stippling typically affects the long bones in the arms and legs, the ribs, the spinal bones (vertebrae), and the cartilage that makes up the windpipe (trachea). The stippling is apparent in infancy but disappears in early childhood. Other skeletal abnormalities seen in people with X-linked chondrodysplasia punctata 2 include shortening of the bones in the upper arms and thighs (rhizomelia) that is often different on the right and left sides, and progressive abnormal curvature of the spine (kyphoscoliosis). As a result of these abnormalities, people with this condition tend to have short stature. Infants with X-linked chondrodysplasia punctata 2 are born with dry, scaly patches of skin (ichthyosis) in a linear or spiral (whorled) pattern. The scaly patches fade over time, leaving abnormally colored blotches of skin without hair (follicular atrophoderma). Most affected individuals also have sparse, coarse hair on their scalps. Most people with X-linked chondrodysplasia punctata 2 have clouding of the lens of the eye (cataracts) from birth or early childhood. Other eye abnormalities that have been associated with this disorder include unusually small eyes (microphthalmia) and small corneas (microcornea). The cornea is the clear front surface of the eye. These eye abnormalities can impair vision. In affected females, X-linked chondrodysplasia punctata 2 is typically associated with normal intelligence and a normal lifespan. However, a much more severe form of the condition has been reported in a small number of males. Affected males have some of the same features as affected females, as well as weak muscle tone (hypotonia), changes in the structure of the brain, moderately to profoundly delayed development, seizures, distinctive facial features, and other birth defects. The health problems associated with X-linked chondrodysplasia punctata 2 are often life-threatening in males. X-linked chondrodysplasia punctata 2 has been estimated to affect fewer than 1 in 400,000 newborns. However, the disorder may actually be more common than this estimate because it is likely underdiagnosed, particularly in females with mild signs and symptoms. More than 95 percent of cases of X-linked chondrodysplasia punctata 2 occur in females. About a dozen males with the condition have been reported in the scientific literature. X-linked chondrodysplasia punctata 2 is caused by mutations in the EBP gene. This gene provides instructions for making an enzyme called 3β-hydroxysteroid-Î8,Î7-isomerase, which is responsible for one of the final steps in the production of cholesterol. Cholesterol is a waxy, fat-like substance that is produced in the body and obtained from foods that come from animals (particularly egg yolks, meat, poultry, fish, and dairy products). Although too much cholesterol is a risk factor for heart disease, this molecule is necessary for normal embryonic development and has important functions both before and after birth. It is a structural component of cell membranes and plays a role in the production of certain hormones and digestive acids. Mutations in the EBP gene reduce the activity of 3β-hydroxysteroid-Î8,Î7-isomerase, preventing cells from producing enough cholesterol. A shortage of this enzyme also allows potentially toxic byproducts of cholesterol production to build up in the body. The combination of low cholesterol levels and an accumulation of other substances likely disrupts the growth and development of many body systems. It is not known, however, how this disturbance in cholesterol production leads to the specific features of X-linked chondrodysplasia punctata 2. This condition is inherited in an X-linked dominant pattern. The gene associated with this condition is located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a mutation in one of the two copies of the EBP gene in each cell is sufficient to cause the disorder. Some cells produce a normal amount of 3β-hydroxysteroid-Î8,Î7-isomerase and other cells produce none. The resulting overall reduction in the amount of this enzyme underlies the signs and symptoms of X-linked chondrodysplasia punctata 2. In males (who have only one X chromosome), a mutation in the EBP gene can result in a total loss of 3β-hydroxysteroid-Î8,Î7-isomerase. A complete lack of this enzyme is usually lethal in the early stages of development, so few males have been born with X-linked chondrodysplasia punctata 2. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is X-linked chondrodysplasia punctata 2 inherited ? | This condition is inherited in an X-linked dominant pattern. The gene associated with this condition is located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a mutation in one of the two copies of the EBP gene in each cell is sufficient to cause the disorder. Some cells produce a normal amount of 3-hydroxysteroid-8,7-isomerase and other cells produce none. The resulting overall reduction in the amount of this enzyme underlies the signs and symptoms of X-linked chondrodysplasia punctata 2. In males (who have only one X chromosome), a mutation in the EBP gene can result in a total loss of 3-hydroxysteroid-8,7-isomerase. A complete lack of this enzyme is usually lethal in the early stages of development, so few males have been born with X-linked chondrodysplasia punctata 2. |
X-linked chondrodysplasia punctata 2 is a disorder characterized by bone, skin, and eye abnormalities. It occurs almost exclusively in females. Although the signs and symptoms of this condition vary widely, almost all affected individuals have chondrodysplasia punctata, an abnormality that appears on x-rays as spots (stippling) near the ends of bones and in cartilage. In this form of chondrodysplasia punctata, the stippling typically affects the long bones in the arms and legs, the ribs, the spinal bones (vertebrae), and the cartilage that makes up the windpipe (trachea). The stippling is apparent in infancy but disappears in early childhood. Other skeletal abnormalities seen in people with X-linked chondrodysplasia punctata 2 include shortening of the bones in the upper arms and thighs (rhizomelia) that is often different on the right and left sides, and progressive abnormal curvature of the spine (kyphoscoliosis). As a result of these abnormalities, people with this condition tend to have short stature. Infants with X-linked chondrodysplasia punctata 2 are born with dry, scaly patches of skin (ichthyosis) in a linear or spiral (whorled) pattern. The scaly patches fade over time, leaving abnormally colored blotches of skin without hair (follicular atrophoderma). Most affected individuals also have sparse, coarse hair on their scalps. Most people with X-linked chondrodysplasia punctata 2 have clouding of the lens of the eye (cataracts) from birth or early childhood. Other eye abnormalities that have been associated with this disorder include unusually small eyes (microphthalmia) and small corneas (microcornea). The cornea is the clear front surface of the eye. These eye abnormalities can impair vision. In affected females, X-linked chondrodysplasia punctata 2 is typically associated with normal intelligence and a normal lifespan. However, a much more severe form of the condition has been reported in a small number of males. Affected males have some of the same features as affected females, as well as weak muscle tone (hypotonia), changes in the structure of the brain, moderately to profoundly delayed development, seizures, distinctive facial features, and other birth defects. The health problems associated with X-linked chondrodysplasia punctata 2 are often life-threatening in males. X-linked chondrodysplasia punctata 2 has been estimated to affect fewer than 1 in 400,000 newborns. However, the disorder may actually be more common than this estimate because it is likely underdiagnosed, particularly in females with mild signs and symptoms. More than 95 percent of cases of X-linked chondrodysplasia punctata 2 occur in females. About a dozen males with the condition have been reported in the scientific literature. X-linked chondrodysplasia punctata 2 is caused by mutations in the EBP gene. This gene provides instructions for making an enzyme called 3β-hydroxysteroid-Î8,Î7-isomerase, which is responsible for one of the final steps in the production of cholesterol. Cholesterol is a waxy, fat-like substance that is produced in the body and obtained from foods that come from animals (particularly egg yolks, meat, poultry, fish, and dairy products). Although too much cholesterol is a risk factor for heart disease, this molecule is necessary for normal embryonic development and has important functions both before and after birth. It is a structural component of cell membranes and plays a role in the production of certain hormones and digestive acids. Mutations in the EBP gene reduce the activity of 3β-hydroxysteroid-Î8,Î7-isomerase, preventing cells from producing enough cholesterol. A shortage of this enzyme also allows potentially toxic byproducts of cholesterol production to build up in the body. The combination of low cholesterol levels and an accumulation of other substances likely disrupts the growth and development of many body systems. It is not known, however, how this disturbance in cholesterol production leads to the specific features of X-linked chondrodysplasia punctata 2. This condition is inherited in an X-linked dominant pattern. The gene associated with this condition is located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a mutation in one of the two copies of the EBP gene in each cell is sufficient to cause the disorder. Some cells produce a normal amount of 3β-hydroxysteroid-Î8,Î7-isomerase and other cells produce none. The resulting overall reduction in the amount of this enzyme underlies the signs and symptoms of X-linked chondrodysplasia punctata 2. In males (who have only one X chromosome), a mutation in the EBP gene can result in a total loss of 3β-hydroxysteroid-Î8,Î7-isomerase. A complete lack of this enzyme is usually lethal in the early stages of development, so few males have been born with X-linked chondrodysplasia punctata 2. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for X-linked chondrodysplasia punctata 2 ? | These resources address the diagnosis or management of X-linked chondrodysplasia punctata 2: - Gene Review: Gene Review: Chondrodysplasia Punctata 2, X-Linked - Genetic Testing Registry: Chondrodysplasia punctata 2 X-linked dominant These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Or, try one of these pages: If you need help, see our site map or contact us. | What is (are) DMD-associated dilated cardiomyopathy ? | DMD-associated dilated cardiomyopathy is a form of heart disease that is caused by mutations in the DMD gene. Dilated cardiomyopathy enlarges and weakens the heart (cardiac) muscle, preventing the heart from pumping blood efficiently. Signs and symptoms of this condition can include an irregular heartbeat (arrhythmia), shortness of breath, extreme tiredness (fatigue), and swelling of the legs and feet. In males with DMD-associated dilated cardiomyopathy, heart problems usually develop early in life and worsen quickly, leading to heart failure in adolescence or early adulthood. In affected females, the condition appears later in life and worsens more slowly. Dilated cardiomyopathy is a feature of two related conditions that are also caused by mutations in the DMD gene: Duchenne and Becker muscular dystrophy. In addition to heart disease, these conditions are characterized by progressive weakness and wasting of muscles used for movement (skeletal muscles). People with DMD-associated dilated cardiomyopathy typically do not have any skeletal muscle weakness or wasting, although they may have subtle changes in their skeletal muscle cells that are detectable through laboratory testing. Based on these skeletal muscle changes, DMD-associated dilated cardiomyopathy is sometimes classified as subclinical Becker muscular dystrophy. |
Or, try one of these pages: If you need help, see our site map or contact us. | How many people are affected by DMD-associated dilated cardiomyopathy ? | DMD-associated dilated cardiomyopathy appears to be an uncommon condition, although its prevalence is unknown. |
Or, try one of these pages: If you need help, see our site map or contact us. | What are the genetic changes related to DMD-associated dilated cardiomyopathy ? | DMD-associated dilated cardiomyopathy results from mutations in the DMD gene. This gene provides instructions for making a protein called dystrophin, which helps stabilize and protect muscle fibers and may play a role in chemical signaling within cells. The mutations responsible for DMD-associated dilated cardiomyopathy preferentially affect the activity of dystrophin in cardiac muscle cells. As a result of these mutations, affected individuals typically have little or no functional dystrophin in the heart. Without enough of this protein, cardiac muscle cells become damaged as the heart muscle repeatedly contracts and relaxes. The damaged muscle cells weaken and die over time, leading to the heart problems characteristic of DMD-associated dilated cardiomyopathy. The mutations that cause DMD-associated dilated cardiomyopathy often lead to reduced amounts of dystrophin in skeletal muscle cells. However, enough of this protein is present to prevent weakness and wasting of the skeletal muscles. Because DMD-associated dilated cardiomyopathy results from a shortage of dystrophin, it is classified as a dystrophinopathy. |
Or, try one of these pages: If you need help, see our site map or contact us. | Is DMD-associated dilated cardiomyopathy inherited ? | DMD-associated dilated cardiomyopathy has an X-linked pattern of inheritance. The DMD gene is located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a mutation in one of the two copies of the gene in each cell usually leads to relatively mild heart disease that appears later in life. In males (who have only one X chromosome), a mutation in the only copy of the gene in each cell causes more severe signs and symptoms that occur earlier in life. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. |
Or, try one of these pages: If you need help, see our site map or contact us. | What are the treatments for DMD-associated dilated cardiomyopathy ? | These resources address the diagnosis or management of DMD-associated dilated cardiomyopathy: - Gene Review: Gene Review: Dilated Cardiomyopathy Overview - Gene Review: Gene Review: Dystrophinopathies - Genetic Testing Registry: Dilated cardiomyopathy 3B - Genetic Testing Registry: Duchenne muscular dystrophy - National Heart, Lung, and Blood Institute: How Is Cardiomyopathy Diagnosed? - National Heart, Lung, and Blood Institute: How Is Cardiomyopathy Treated? These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Ollier disease is a disorder characterized by multiple enchondromas, which are noncancerous (benign) growths of cartilage that develop within the bones. These growths most commonly occur in the limb bones, especially in the bones of the hands and feet; however, they may also occur in the skull, ribs, and bones of the spine (vertebrae). Enchondromas may result in severe bone deformities, shortening of the limbs, and fractures. The signs and symptoms of Ollier disease may be detectable at birth, although they generally do not become apparent until around the age of 5. Enchondromas develop near the ends of bones, where normal growth occurs, and they frequently stop forming after affected individuals stop growing in early adulthood. As a result of the bone deformities associated with Ollier disease, people with this disorder generally have short stature and underdeveloped muscles. Although the enchondromas associated with Ollier disease start out as benign, they may become cancerous (malignant). In particular, affected individuals may develop bone cancers called chondrosarcomas, especially in the skull. People with Ollier disease also have an increased risk of other cancers, such as ovarian cancer or liver cancer. People with Ollier disease usually have a normal lifespan, and intelligence is unaffected. The extent of their physical impairment depends on their individual skeletal deformities, but in most cases they have no major limitations in their activities. A related disorder called Maffucci syndrome also involves multiple enchondromas but is distinguished by the presence of red or purplish growths in the skin consisting of tangles of abnormal blood vessels (hemangiomas). Ollier disease is estimated to occur in 1 in 100,000 people. In most people with Ollier disease, the disorder is caused by mutations in the IDH1 or IDH2 gene. These genes provide instructions for making enzymes called isocitrate dehydrogenase 1 and isocitrate dehydrogenase 2, respectively. These enzymes convert a compound called isocitrate to another compound called 2-ketoglutarate. This reaction also produces a molecule called NADPH, which is necessary for many cellular processes. IDH1 or IDH2 gene mutations cause the enzyme produced from the respective gene to take on a new, abnormal function. Although these mutations have been found in some cells of enchondromas in people with Ollier disease, the relationship between the mutations and the signs and symptoms of the disorder is not well understood. Mutations in other genes may also account for some cases of Ollier disease. Ollier disease is not inherited. The mutations that cause this disorder are somatic, which means they occur during a person's lifetime. A somatic mutation occurs in a single cell. As that cell continues to grow and divide, the cells derived from it also have the same mutation. In Ollier disease, the mutation is thought to occur in a cell during early development before birth; cells that arise from that abnormal cell have the mutation, while the body's other cells do not. This situation is called mosaicism. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) Ollier disease ? | Ollier disease is a disorder characterized by multiple enchondromas, which are noncancerous (benign) growths of cartilage that develop within the bones. These growths most commonly occur in the limb bones, especially in the bones of the hands and feet; however, they may also occur in the skull, ribs, and bones of the spine (vertebrae). Enchondromas may result in severe bone deformities, shortening of the limbs, and fractures. The signs and symptoms of Ollier disease may be detectable at birth, although they generally do not become apparent until around the age of 5. Enchondromas develop near the ends of bones, where normal growth occurs, and they frequently stop forming after affected individuals stop growing in early adulthood. As a result of the bone deformities associated with Ollier disease, people with this disorder generally have short stature and underdeveloped muscles. Although the enchondromas associated with Ollier disease start out as benign, they may become cancerous (malignant). In particular, affected individuals may develop bone cancers called chondrosarcomas, especially in the skull. People with Ollier disease also have an increased risk of other cancers, such as ovarian or liver cancer. People with Ollier disease usually have a normal lifespan, and intelligence is unaffected. The extent of their physical impairment depends on their individual skeletal deformities, but in most cases they have no major limitations in their activities. A related disorder called Maffucci syndrome also involves multiple enchondromas but is distinguished by the presence of red or purplish growths in the skin consisting of tangles of abnormal blood vessels (hemangiomas). |
Ollier disease is a disorder characterized by multiple enchondromas, which are noncancerous (benign) growths of cartilage that develop within the bones. These growths most commonly occur in the limb bones, especially in the bones of the hands and feet; however, they may also occur in the skull, ribs, and bones of the spine (vertebrae). Enchondromas may result in severe bone deformities, shortening of the limbs, and fractures. The signs and symptoms of Ollier disease may be detectable at birth, although they generally do not become apparent until around the age of 5. Enchondromas develop near the ends of bones, where normal growth occurs, and they frequently stop forming after affected individuals stop growing in early adulthood. As a result of the bone deformities associated with Ollier disease, people with this disorder generally have short stature and underdeveloped muscles. Although the enchondromas associated with Ollier disease start out as benign, they may become cancerous (malignant). In particular, affected individuals may develop bone cancers called chondrosarcomas, especially in the skull. People with Ollier disease also have an increased risk of other cancers, such as ovarian cancer or liver cancer. People with Ollier disease usually have a normal lifespan, and intelligence is unaffected. The extent of their physical impairment depends on their individual skeletal deformities, but in most cases they have no major limitations in their activities. A related disorder called Maffucci syndrome also involves multiple enchondromas but is distinguished by the presence of red or purplish growths in the skin consisting of tangles of abnormal blood vessels (hemangiomas). Ollier disease is estimated to occur in 1 in 100,000 people. In most people with Ollier disease, the disorder is caused by mutations in the IDH1 or IDH2 gene. These genes provide instructions for making enzymes called isocitrate dehydrogenase 1 and isocitrate dehydrogenase 2, respectively. These enzymes convert a compound called isocitrate to another compound called 2-ketoglutarate. This reaction also produces a molecule called NADPH, which is necessary for many cellular processes. IDH1 or IDH2 gene mutations cause the enzyme produced from the respective gene to take on a new, abnormal function. Although these mutations have been found in some cells of enchondromas in people with Ollier disease, the relationship between the mutations and the signs and symptoms of the disorder is not well understood. Mutations in other genes may also account for some cases of Ollier disease. Ollier disease is not inherited. The mutations that cause this disorder are somatic, which means they occur during a person's lifetime. A somatic mutation occurs in a single cell. As that cell continues to grow and divide, the cells derived from it also have the same mutation. In Ollier disease, the mutation is thought to occur in a cell during early development before birth; cells that arise from that abnormal cell have the mutation, while the body's other cells do not. This situation is called mosaicism. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by Ollier disease ? | Ollier disease is estimated to occur in 1 in 100,000 people. |
Ollier disease is a disorder characterized by multiple enchondromas, which are noncancerous (benign) growths of cartilage that develop within the bones. These growths most commonly occur in the limb bones, especially in the bones of the hands and feet; however, they may also occur in the skull, ribs, and bones of the spine (vertebrae). Enchondromas may result in severe bone deformities, shortening of the limbs, and fractures. The signs and symptoms of Ollier disease may be detectable at birth, although they generally do not become apparent until around the age of 5. Enchondromas develop near the ends of bones, where normal growth occurs, and they frequently stop forming after affected individuals stop growing in early adulthood. As a result of the bone deformities associated with Ollier disease, people with this disorder generally have short stature and underdeveloped muscles. Although the enchondromas associated with Ollier disease start out as benign, they may become cancerous (malignant). In particular, affected individuals may develop bone cancers called chondrosarcomas, especially in the skull. People with Ollier disease also have an increased risk of other cancers, such as ovarian cancer or liver cancer. People with Ollier disease usually have a normal lifespan, and intelligence is unaffected. The extent of their physical impairment depends on their individual skeletal deformities, but in most cases they have no major limitations in their activities. A related disorder called Maffucci syndrome also involves multiple enchondromas but is distinguished by the presence of red or purplish growths in the skin consisting of tangles of abnormal blood vessels (hemangiomas). Ollier disease is estimated to occur in 1 in 100,000 people. In most people with Ollier disease, the disorder is caused by mutations in the IDH1 or IDH2 gene. These genes provide instructions for making enzymes called isocitrate dehydrogenase 1 and isocitrate dehydrogenase 2, respectively. These enzymes convert a compound called isocitrate to another compound called 2-ketoglutarate. This reaction also produces a molecule called NADPH, which is necessary for many cellular processes. IDH1 or IDH2 gene mutations cause the enzyme produced from the respective gene to take on a new, abnormal function. Although these mutations have been found in some cells of enchondromas in people with Ollier disease, the relationship between the mutations and the signs and symptoms of the disorder is not well understood. Mutations in other genes may also account for some cases of Ollier disease. Ollier disease is not inherited. The mutations that cause this disorder are somatic, which means they occur during a person's lifetime. A somatic mutation occurs in a single cell. As that cell continues to grow and divide, the cells derived from it also have the same mutation. In Ollier disease, the mutation is thought to occur in a cell during early development before birth; cells that arise from that abnormal cell have the mutation, while the body's other cells do not. This situation is called mosaicism. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to Ollier disease ? | In most people with Ollier disease, the disorder is caused by mutations in the IDH1 or IDH2 gene. These genes provide instructions for making enzymes called isocitrate dehydrogenase 1 and isocitrate dehydrogenase 2, respectively. These enzymes convert a compound called isocitrate to another compound called 2-ketoglutarate. This reaction also produces a molecule called NADPH, which is necessary for many cellular processes. IDH1 or IDH2 gene mutations cause the enzyme produced from the respective gene to take on a new, abnormal function. Although these mutations have been found in some cells of enchondromas in people with Ollier disease, the relationship between the mutations and the signs and symptoms of the disorder is not well understood. Mutations in other genes may also account for some cases of Ollier disease. |
Ollier disease is a disorder characterized by multiple enchondromas, which are noncancerous (benign) growths of cartilage that develop within the bones. These growths most commonly occur in the limb bones, especially in the bones of the hands and feet; however, they may also occur in the skull, ribs, and bones of the spine (vertebrae). Enchondromas may result in severe bone deformities, shortening of the limbs, and fractures. The signs and symptoms of Ollier disease may be detectable at birth, although they generally do not become apparent until around the age of 5. Enchondromas develop near the ends of bones, where normal growth occurs, and they frequently stop forming after affected individuals stop growing in early adulthood. As a result of the bone deformities associated with Ollier disease, people with this disorder generally have short stature and underdeveloped muscles. Although the enchondromas associated with Ollier disease start out as benign, they may become cancerous (malignant). In particular, affected individuals may develop bone cancers called chondrosarcomas, especially in the skull. People with Ollier disease also have an increased risk of other cancers, such as ovarian cancer or liver cancer. People with Ollier disease usually have a normal lifespan, and intelligence is unaffected. The extent of their physical impairment depends on their individual skeletal deformities, but in most cases they have no major limitations in their activities. A related disorder called Maffucci syndrome also involves multiple enchondromas but is distinguished by the presence of red or purplish growths in the skin consisting of tangles of abnormal blood vessels (hemangiomas). Ollier disease is estimated to occur in 1 in 100,000 people. In most people with Ollier disease, the disorder is caused by mutations in the IDH1 or IDH2 gene. These genes provide instructions for making enzymes called isocitrate dehydrogenase 1 and isocitrate dehydrogenase 2, respectively. These enzymes convert a compound called isocitrate to another compound called 2-ketoglutarate. This reaction also produces a molecule called NADPH, which is necessary for many cellular processes. IDH1 or IDH2 gene mutations cause the enzyme produced from the respective gene to take on a new, abnormal function. Although these mutations have been found in some cells of enchondromas in people with Ollier disease, the relationship between the mutations and the signs and symptoms of the disorder is not well understood. Mutations in other genes may also account for some cases of Ollier disease. Ollier disease is not inherited. The mutations that cause this disorder are somatic, which means they occur during a person's lifetime. A somatic mutation occurs in a single cell. As that cell continues to grow and divide, the cells derived from it also have the same mutation. In Ollier disease, the mutation is thought to occur in a cell during early development before birth; cells that arise from that abnormal cell have the mutation, while the body's other cells do not. This situation is called mosaicism. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is Ollier disease inherited ? | Ollier disease is not inherited. The mutations that cause this disorder are somatic, which means they occur during a person's lifetime. A somatic mutation occurs in a single cell. As that cell continues to grow and divide, the cells derived from it also have the same mutation. In Ollier disease, the mutation is thought to occur in a cell during early development before birth; cells that arise from that abnormal cell have the mutation, while the body's other cells do not. This situation is called mosaicism. |
Ollier disease is a disorder characterized by multiple enchondromas, which are noncancerous (benign) growths of cartilage that develop within the bones. These growths most commonly occur in the limb bones, especially in the bones of the hands and feet; however, they may also occur in the skull, ribs, and bones of the spine (vertebrae). Enchondromas may result in severe bone deformities, shortening of the limbs, and fractures. The signs and symptoms of Ollier disease may be detectable at birth, although they generally do not become apparent until around the age of 5. Enchondromas develop near the ends of bones, where normal growth occurs, and they frequently stop forming after affected individuals stop growing in early adulthood. As a result of the bone deformities associated with Ollier disease, people with this disorder generally have short stature and underdeveloped muscles. Although the enchondromas associated with Ollier disease start out as benign, they may become cancerous (malignant). In particular, affected individuals may develop bone cancers called chondrosarcomas, especially in the skull. People with Ollier disease also have an increased risk of other cancers, such as ovarian cancer or liver cancer. People with Ollier disease usually have a normal lifespan, and intelligence is unaffected. The extent of their physical impairment depends on their individual skeletal deformities, but in most cases they have no major limitations in their activities. A related disorder called Maffucci syndrome also involves multiple enchondromas but is distinguished by the presence of red or purplish growths in the skin consisting of tangles of abnormal blood vessels (hemangiomas). Ollier disease is estimated to occur in 1 in 100,000 people. In most people with Ollier disease, the disorder is caused by mutations in the IDH1 or IDH2 gene. These genes provide instructions for making enzymes called isocitrate dehydrogenase 1 and isocitrate dehydrogenase 2, respectively. These enzymes convert a compound called isocitrate to another compound called 2-ketoglutarate. This reaction also produces a molecule called NADPH, which is necessary for many cellular processes. IDH1 or IDH2 gene mutations cause the enzyme produced from the respective gene to take on a new, abnormal function. Although these mutations have been found in some cells of enchondromas in people with Ollier disease, the relationship between the mutations and the signs and symptoms of the disorder is not well understood. Mutations in other genes may also account for some cases of Ollier disease. Ollier disease is not inherited. The mutations that cause this disorder are somatic, which means they occur during a person's lifetime. A somatic mutation occurs in a single cell. As that cell continues to grow and divide, the cells derived from it also have the same mutation. In Ollier disease, the mutation is thought to occur in a cell during early development before birth; cells that arise from that abnormal cell have the mutation, while the body's other cells do not. This situation is called mosaicism. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for Ollier disease ? | These resources address the diagnosis or management of Ollier disease: - Genetic Testing Registry: Enchondromatosis These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Timothy syndrome is a rare disorder that primarily affects the heart but can affect many other areas of the body. The severity of this condition varies among affected individuals, although it is often life-threatening. Timothy syndrome is characterized by a heart condition called long QT syndrome, which causes the heart (cardiac) muscle to take longer than usual to recharge between beats. This abnormality in the heart's electrical system can cause severe abnormalities of the heart rhythm (arrhythmias), which can lead to sudden death. Some people with Timothy syndrome are also born with structural heart defects (cardiomyopathy) that affect the heart's ability to pump blood effectively. As a result of these serious heart problems, some people with Timothy syndrome live only into childhood. In about 80 percent of cases of Timothy syndrome, the cause of death is a severe form of arrhythmia called ventricular tachycardia, in which the lower chambers of the heart (the ventricles) beat abnormally fast, often leading to cardiac arrest (the heart suddenly stops beating) and sudden death. Timothy syndrome is also characterized by webbing or fusion of the skin between some fingers or toes (cutaneous syndactyly). About half of affected people have distinctive facial features such as a flattened nasal bridge, low-set ears, a small upper jaw, and a thin upper lip. Children with this condition have small, misplaced teeth and frequent cavities (dental caries). Additional signs and symptoms of Timothy syndrome can include baldness at birth, low muscle tone (hypotonia), frequent infections, episodes of low blood sugar (hypoglycemia), and an abnormally low body temperature (hypothermia). The respiratory system and gastrointestinal tract can also be affected. Neuropsychiatric features are also common in individuals with Timothy syndrome. Researchers have found that many children with Timothy syndrome have the characteristic features of autism spectrum disorders. Affected children tend to have impaired communication and socialization skills, as well as delayed development of speech and language. Poor coordination is also frequent in affected individuals. Other nervous system disorders that can occur in Timothy syndrome include attention-deficit/hyperactivity disorder, intellectual disability and recurrent seizures (epilepsy); some affected individuals have photosensitive epilepsy, in which seizures are triggered by flashing lights. Timothy syndrome is a rare condition; fewer than 100 people with this disorder have been reported worldwide. Variants (also known as mutations) in the CACNA1C gene cause Timothy syndrome. This gene provides instructions for making a protein that acts as a small hole or pore (a channel) across cell membranes. This channel, known as CaV1.2, transports positively charged calcium atoms (calcium ions) into cardiac cells (cardiomyocytes) and nerve cells (neurons) in the brain. Calcium ions are important for many cellular functions, including regulating the electrical activity of cells, cell-to-cell communication, the tensing of muscle fibers (muscle contraction), and the regulation of certain genes, particularly those involved in the development of the brain and bones before birth. Variants in the CACNA1C gene that cause Timothy syndrome change the structure of CaV1.2 channels. These gene changes lead to altered channels that stay open much longer than usual, which allows calcium ions to continue flowing into cells abnormally. The resulting overload of calcium ions within cardiac muscle cells changes the way the heart beats and can cause abnormal heart muscle contractions and arrhythmia. It is thought that the altered channels and flow of calcium ions also impair regulation of certain genes, resulting in the facial, dental, and neurological abnormalities in Timothy syndrome. Other variants in the CACNA1C gene can cause isolated features of Timothy syndrome without the other associated health problems of the condition. For example, some people with CACNA1C gene variants may have only long QT syndrome or only neurodevelopmental disorders. This condition is considered to have an autosomal dominant pattern of inheritance, which means one copy of the altered CACNA1C gene in each cell is sufficient to cause the disorder. Most cases result from new (de novo) variants in the gene. In these cases, there is no history of the disorder in their family. Because of the severity of Timothy syndrome, it is rare for an affected individual to be able to pass on the disease-causing variant. Although rare, some people with Timothy syndrome inherit the altered gene from an unaffected parent who is mosaic for a CACNA1C gene variant. Mosaicism means that the parent has the variant in some cells (including egg or sperm cells), but not in others. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) Timothy syndrome ? | Timothy syndrome is a rare disorder that affects many parts of the body including the heart, digits (fingers and toes), and the nervous system. Timothy syndrome is characterized by a heart condition called long QT syndrome, which causes the heart (cardiac) muscle to take longer than usual to recharge between beats. This abnormality in the heart's electrical system can cause irregular heartbeats (arrhythmia), which can lead to sudden death. Many people with Timothy syndrome are also born with structural heart defects that affect the heart's ability to pump blood effectively. As a result of these serious heart problems, many people with Timothy syndrome live only into childhood. The most common cause of death is a form of arrhythmia called ventricular tachyarrhythmia, in which the lower chambers of the heart (the ventricles) beat abnormally fast and lead to cardiac arrest. Timothy syndrome is also characterized by webbing or fusion of the skin between some fingers or toes (cutaneous syndactyly). About half of affected people have distinctive facial features such as a flattened nasal bridge, low-set ears, a small upper jaw, and a thin upper lip. Children with this condition have small, misplaced teeth and frequent cavities (dental caries). Additional signs and symptoms of Timothy syndrome can include baldness at birth, frequent infections, episodes of low blood sugar (hypoglycemia), and an abnormally low body temperature (hypothermia). Researchers have found that many children with Timothy syndrome have the characteristic features of autism or similar conditions known as autistic spectrum disorders. Affected children tend to have impaired communication and socialization skills, as well as delayed development of speech and language. Other nervous system abnormalities, including intellectual disability and seizures, can also occur in children with Timothy syndrome. Researchers have identified two forms of Timothy syndrome. Type 1, which is also known as the classic type, includes all of the characteristic features described above. Type 2, or the atypical type, causes a more severe form of long QT syndrome and a greater risk of arrhythmia and sudden death. Unlike the classic type, the atypical type does not appear to cause webbing of the fingers or toes. |
Timothy syndrome is a rare disorder that primarily affects the heart but can affect many other areas of the body. The severity of this condition varies among affected individuals, although it is often life-threatening. Timothy syndrome is characterized by a heart condition called long QT syndrome, which causes the heart (cardiac) muscle to take longer than usual to recharge between beats. This abnormality in the heart's electrical system can cause severe abnormalities of the heart rhythm (arrhythmias), which can lead to sudden death. Some people with Timothy syndrome are also born with structural heart defects (cardiomyopathy) that affect the heart's ability to pump blood effectively. As a result of these serious heart problems, some people with Timothy syndrome live only into childhood. In about 80 percent of cases of Timothy syndrome, the cause of death is a severe form of arrhythmia called ventricular tachycardia, in which the lower chambers of the heart (the ventricles) beat abnormally fast, often leading to cardiac arrest (the heart suddenly stops beating) and sudden death. Timothy syndrome is also characterized by webbing or fusion of the skin between some fingers or toes (cutaneous syndactyly). About half of affected people have distinctive facial features such as a flattened nasal bridge, low-set ears, a small upper jaw, and a thin upper lip. Children with this condition have small, misplaced teeth and frequent cavities (dental caries). Additional signs and symptoms of Timothy syndrome can include baldness at birth, low muscle tone (hypotonia), frequent infections, episodes of low blood sugar (hypoglycemia), and an abnormally low body temperature (hypothermia). The respiratory system and gastrointestinal tract can also be affected. Neuropsychiatric features are also common in individuals with Timothy syndrome. Researchers have found that many children with Timothy syndrome have the characteristic features of autism spectrum disorders. Affected children tend to have impaired communication and socialization skills, as well as delayed development of speech and language. Poor coordination is also frequent in affected individuals. Other nervous system disorders that can occur in Timothy syndrome include attention-deficit/hyperactivity disorder, intellectual disability and recurrent seizures (epilepsy); some affected individuals have photosensitive epilepsy, in which seizures are triggered by flashing lights. Timothy syndrome is a rare condition; fewer than 100 people with this disorder have been reported worldwide. Variants (also known as mutations) in the CACNA1C gene cause Timothy syndrome. This gene provides instructions for making a protein that acts as a small hole or pore (a channel) across cell membranes. This channel, known as CaV1.2, transports positively charged calcium atoms (calcium ions) into cardiac cells (cardiomyocytes) and nerve cells (neurons) in the brain. Calcium ions are important for many cellular functions, including regulating the electrical activity of cells, cell-to-cell communication, the tensing of muscle fibers (muscle contraction), and the regulation of certain genes, particularly those involved in the development of the brain and bones before birth. Variants in the CACNA1C gene that cause Timothy syndrome change the structure of CaV1.2 channels. These gene changes lead to altered channels that stay open much longer than usual, which allows calcium ions to continue flowing into cells abnormally. The resulting overload of calcium ions within cardiac muscle cells changes the way the heart beats and can cause abnormal heart muscle contractions and arrhythmia. It is thought that the altered channels and flow of calcium ions also impair regulation of certain genes, resulting in the facial, dental, and neurological abnormalities in Timothy syndrome. Other variants in the CACNA1C gene can cause isolated features of Timothy syndrome without the other associated health problems of the condition. For example, some people with CACNA1C gene variants may have only long QT syndrome or only neurodevelopmental disorders. This condition is considered to have an autosomal dominant pattern of inheritance, which means one copy of the altered CACNA1C gene in each cell is sufficient to cause the disorder. Most cases result from new (de novo) variants in the gene. In these cases, there is no history of the disorder in their family. Because of the severity of Timothy syndrome, it is rare for an affected individual to be able to pass on the disease-causing variant. Although rare, some people with Timothy syndrome inherit the altered gene from an unaffected parent who is mosaic for a CACNA1C gene variant. Mosaicism means that the parent has the variant in some cells (including egg or sperm cells), but not in others. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by Timothy syndrome ? | Timothy syndrome is a rare condition; fewer than 20 people with this disorder have been reported worldwide. The classic type of Timothy syndrome appears to be more common than the atypical type, which has been identified in only two individuals. |
Timothy syndrome is a rare disorder that primarily affects the heart but can affect many other areas of the body. The severity of this condition varies among affected individuals, although it is often life-threatening. Timothy syndrome is characterized by a heart condition called long QT syndrome, which causes the heart (cardiac) muscle to take longer than usual to recharge between beats. This abnormality in the heart's electrical system can cause severe abnormalities of the heart rhythm (arrhythmias), which can lead to sudden death. Some people with Timothy syndrome are also born with structural heart defects (cardiomyopathy) that affect the heart's ability to pump blood effectively. As a result of these serious heart problems, some people with Timothy syndrome live only into childhood. In about 80 percent of cases of Timothy syndrome, the cause of death is a severe form of arrhythmia called ventricular tachycardia, in which the lower chambers of the heart (the ventricles) beat abnormally fast, often leading to cardiac arrest (the heart suddenly stops beating) and sudden death. Timothy syndrome is also characterized by webbing or fusion of the skin between some fingers or toes (cutaneous syndactyly). About half of affected people have distinctive facial features such as a flattened nasal bridge, low-set ears, a small upper jaw, and a thin upper lip. Children with this condition have small, misplaced teeth and frequent cavities (dental caries). Additional signs and symptoms of Timothy syndrome can include baldness at birth, low muscle tone (hypotonia), frequent infections, episodes of low blood sugar (hypoglycemia), and an abnormally low body temperature (hypothermia). The respiratory system and gastrointestinal tract can also be affected. Neuropsychiatric features are also common in individuals with Timothy syndrome. Researchers have found that many children with Timothy syndrome have the characteristic features of autism spectrum disorders. Affected children tend to have impaired communication and socialization skills, as well as delayed development of speech and language. Poor coordination is also frequent in affected individuals. Other nervous system disorders that can occur in Timothy syndrome include attention-deficit/hyperactivity disorder, intellectual disability and recurrent seizures (epilepsy); some affected individuals have photosensitive epilepsy, in which seizures are triggered by flashing lights. Timothy syndrome is a rare condition; fewer than 100 people with this disorder have been reported worldwide. Variants (also known as mutations) in the CACNA1C gene cause Timothy syndrome. This gene provides instructions for making a protein that acts as a small hole or pore (a channel) across cell membranes. This channel, known as CaV1.2, transports positively charged calcium atoms (calcium ions) into cardiac cells (cardiomyocytes) and nerve cells (neurons) in the brain. Calcium ions are important for many cellular functions, including regulating the electrical activity of cells, cell-to-cell communication, the tensing of muscle fibers (muscle contraction), and the regulation of certain genes, particularly those involved in the development of the brain and bones before birth. Variants in the CACNA1C gene that cause Timothy syndrome change the structure of CaV1.2 channels. These gene changes lead to altered channels that stay open much longer than usual, which allows calcium ions to continue flowing into cells abnormally. The resulting overload of calcium ions within cardiac muscle cells changes the way the heart beats and can cause abnormal heart muscle contractions and arrhythmia. It is thought that the altered channels and flow of calcium ions also impair regulation of certain genes, resulting in the facial, dental, and neurological abnormalities in Timothy syndrome. Other variants in the CACNA1C gene can cause isolated features of Timothy syndrome without the other associated health problems of the condition. For example, some people with CACNA1C gene variants may have only long QT syndrome or only neurodevelopmental disorders. This condition is considered to have an autosomal dominant pattern of inheritance, which means one copy of the altered CACNA1C gene in each cell is sufficient to cause the disorder. Most cases result from new (de novo) variants in the gene. In these cases, there is no history of the disorder in their family. Because of the severity of Timothy syndrome, it is rare for an affected individual to be able to pass on the disease-causing variant. Although rare, some people with Timothy syndrome inherit the altered gene from an unaffected parent who is mosaic for a CACNA1C gene variant. Mosaicism means that the parent has the variant in some cells (including egg or sperm cells), but not in others. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to Timothy syndrome ? | Mutations in the CACNA1C gene are responsible for all reported cases of Timothy syndrome. This gene provides instructions for making a protein that acts as a channel across cell membranes. This channel, known as CaV1.2, is one of several channels that transport positively charged calcium atoms (calcium ions) into cells. Calcium ions are involved in many different cellular functions, including cell-to-cell communication, the tensing of muscle fibers (muscle contraction), and the regulation of certain genes. CaV1.2 calcium channels are particularly important for the normal function of heart and brain cells. In cardiac muscle, these channels play a critical role in maintaining the heart's normal rhythm. Their role in the brain and in other tissues is less clear. Mutations in the CACNA1C gene change the structure of CaV1.2 channels. The altered channels stay open much longer than usual, which allows calcium ions to continue flowing into cells abnormally. The resulting overload of calcium ions within cardiac muscle cells changes the way the heart beats and can cause arrhythmia. Researchers are working to determine how an increase in calcium ion transport in other tissues, including cells in the brain, underlies the other features of Timothy syndrome. |
Timothy syndrome is a rare disorder that primarily affects the heart but can affect many other areas of the body. The severity of this condition varies among affected individuals, although it is often life-threatening. Timothy syndrome is characterized by a heart condition called long QT syndrome, which causes the heart (cardiac) muscle to take longer than usual to recharge between beats. This abnormality in the heart's electrical system can cause severe abnormalities of the heart rhythm (arrhythmias), which can lead to sudden death. Some people with Timothy syndrome are also born with structural heart defects (cardiomyopathy) that affect the heart's ability to pump blood effectively. As a result of these serious heart problems, some people with Timothy syndrome live only into childhood. In about 80 percent of cases of Timothy syndrome, the cause of death is a severe form of arrhythmia called ventricular tachycardia, in which the lower chambers of the heart (the ventricles) beat abnormally fast, often leading to cardiac arrest (the heart suddenly stops beating) and sudden death. Timothy syndrome is also characterized by webbing or fusion of the skin between some fingers or toes (cutaneous syndactyly). About half of affected people have distinctive facial features such as a flattened nasal bridge, low-set ears, a small upper jaw, and a thin upper lip. Children with this condition have small, misplaced teeth and frequent cavities (dental caries). Additional signs and symptoms of Timothy syndrome can include baldness at birth, low muscle tone (hypotonia), frequent infections, episodes of low blood sugar (hypoglycemia), and an abnormally low body temperature (hypothermia). The respiratory system and gastrointestinal tract can also be affected. Neuropsychiatric features are also common in individuals with Timothy syndrome. Researchers have found that many children with Timothy syndrome have the characteristic features of autism spectrum disorders. Affected children tend to have impaired communication and socialization skills, as well as delayed development of speech and language. Poor coordination is also frequent in affected individuals. Other nervous system disorders that can occur in Timothy syndrome include attention-deficit/hyperactivity disorder, intellectual disability and recurrent seizures (epilepsy); some affected individuals have photosensitive epilepsy, in which seizures are triggered by flashing lights. Timothy syndrome is a rare condition; fewer than 100 people with this disorder have been reported worldwide. Variants (also known as mutations) in the CACNA1C gene cause Timothy syndrome. This gene provides instructions for making a protein that acts as a small hole or pore (a channel) across cell membranes. This channel, known as CaV1.2, transports positively charged calcium atoms (calcium ions) into cardiac cells (cardiomyocytes) and nerve cells (neurons) in the brain. Calcium ions are important for many cellular functions, including regulating the electrical activity of cells, cell-to-cell communication, the tensing of muscle fibers (muscle contraction), and the regulation of certain genes, particularly those involved in the development of the brain and bones before birth. Variants in the CACNA1C gene that cause Timothy syndrome change the structure of CaV1.2 channels. These gene changes lead to altered channels that stay open much longer than usual, which allows calcium ions to continue flowing into cells abnormally. The resulting overload of calcium ions within cardiac muscle cells changes the way the heart beats and can cause abnormal heart muscle contractions and arrhythmia. It is thought that the altered channels and flow of calcium ions also impair regulation of certain genes, resulting in the facial, dental, and neurological abnormalities in Timothy syndrome. Other variants in the CACNA1C gene can cause isolated features of Timothy syndrome without the other associated health problems of the condition. For example, some people with CACNA1C gene variants may have only long QT syndrome or only neurodevelopmental disorders. This condition is considered to have an autosomal dominant pattern of inheritance, which means one copy of the altered CACNA1C gene in each cell is sufficient to cause the disorder. Most cases result from new (de novo) variants in the gene. In these cases, there is no history of the disorder in their family. Because of the severity of Timothy syndrome, it is rare for an affected individual to be able to pass on the disease-causing variant. Although rare, some people with Timothy syndrome inherit the altered gene from an unaffected parent who is mosaic for a CACNA1C gene variant. Mosaicism means that the parent has the variant in some cells (including egg or sperm cells), but not in others. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is Timothy syndrome inherited ? | This condition is considered to have an autosomal dominant pattern of inheritance, which means one copy of the altered CACNA1C gene in each cell is sufficient to cause the disorder. Most cases result from new mutations in the gene, and occur in people with no history of the disorder in their family. Less commonly, people with Timothy syndrome inherit the altered gene from an unaffected parent who is mosaic for a CACNA1C mutation. Mosaicism means that the parent has the mutation in some cells (including egg or sperm cells), but not in others. |
Timothy syndrome is a rare disorder that primarily affects the heart but can affect many other areas of the body. The severity of this condition varies among affected individuals, although it is often life-threatening. Timothy syndrome is characterized by a heart condition called long QT syndrome, which causes the heart (cardiac) muscle to take longer than usual to recharge between beats. This abnormality in the heart's electrical system can cause severe abnormalities of the heart rhythm (arrhythmias), which can lead to sudden death. Some people with Timothy syndrome are also born with structural heart defects (cardiomyopathy) that affect the heart's ability to pump blood effectively. As a result of these serious heart problems, some people with Timothy syndrome live only into childhood. In about 80 percent of cases of Timothy syndrome, the cause of death is a severe form of arrhythmia called ventricular tachycardia, in which the lower chambers of the heart (the ventricles) beat abnormally fast, often leading to cardiac arrest (the heart suddenly stops beating) and sudden death. Timothy syndrome is also characterized by webbing or fusion of the skin between some fingers or toes (cutaneous syndactyly). About half of affected people have distinctive facial features such as a flattened nasal bridge, low-set ears, a small upper jaw, and a thin upper lip. Children with this condition have small, misplaced teeth and frequent cavities (dental caries). Additional signs and symptoms of Timothy syndrome can include baldness at birth, low muscle tone (hypotonia), frequent infections, episodes of low blood sugar (hypoglycemia), and an abnormally low body temperature (hypothermia). The respiratory system and gastrointestinal tract can also be affected. Neuropsychiatric features are also common in individuals with Timothy syndrome. Researchers have found that many children with Timothy syndrome have the characteristic features of autism spectrum disorders. Affected children tend to have impaired communication and socialization skills, as well as delayed development of speech and language. Poor coordination is also frequent in affected individuals. Other nervous system disorders that can occur in Timothy syndrome include attention-deficit/hyperactivity disorder, intellectual disability and recurrent seizures (epilepsy); some affected individuals have photosensitive epilepsy, in which seizures are triggered by flashing lights. Timothy syndrome is a rare condition; fewer than 100 people with this disorder have been reported worldwide. Variants (also known as mutations) in the CACNA1C gene cause Timothy syndrome. This gene provides instructions for making a protein that acts as a small hole or pore (a channel) across cell membranes. This channel, known as CaV1.2, transports positively charged calcium atoms (calcium ions) into cardiac cells (cardiomyocytes) and nerve cells (neurons) in the brain. Calcium ions are important for many cellular functions, including regulating the electrical activity of cells, cell-to-cell communication, the tensing of muscle fibers (muscle contraction), and the regulation of certain genes, particularly those involved in the development of the brain and bones before birth. Variants in the CACNA1C gene that cause Timothy syndrome change the structure of CaV1.2 channels. These gene changes lead to altered channels that stay open much longer than usual, which allows calcium ions to continue flowing into cells abnormally. The resulting overload of calcium ions within cardiac muscle cells changes the way the heart beats and can cause abnormal heart muscle contractions and arrhythmia. It is thought that the altered channels and flow of calcium ions also impair regulation of certain genes, resulting in the facial, dental, and neurological abnormalities in Timothy syndrome. Other variants in the CACNA1C gene can cause isolated features of Timothy syndrome without the other associated health problems of the condition. For example, some people with CACNA1C gene variants may have only long QT syndrome or only neurodevelopmental disorders. This condition is considered to have an autosomal dominant pattern of inheritance, which means one copy of the altered CACNA1C gene in each cell is sufficient to cause the disorder. Most cases result from new (de novo) variants in the gene. In these cases, there is no history of the disorder in their family. Because of the severity of Timothy syndrome, it is rare for an affected individual to be able to pass on the disease-causing variant. Although rare, some people with Timothy syndrome inherit the altered gene from an unaffected parent who is mosaic for a CACNA1C gene variant. Mosaicism means that the parent has the variant in some cells (including egg or sperm cells), but not in others. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for Timothy syndrome ? | These resources address the diagnosis or management of Timothy syndrome: - Gene Review: Gene Review: Timothy Syndrome - Genetic Testing Registry: Timothy syndrome - MedlinePlus Encyclopedia: Arrhythmias - MedlinePlus Encyclopedia: Congenital Heart Disease - MedlinePlus Encyclopedia: Webbing of the Fingers or Toes These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is a condition that prevents the body from converting certain fats to energy, particularly during periods without food (fasting). Signs and symptoms of VLCAD deficiency typically appear during infancy or early childhood and can include low blood sugar (hypoglycemia), lack of energy (lethargy), and muscle weakness. Affected individuals are also at risk for serious complications such as liver abnormalities and life-threatening heart problems. When symptoms begin in adolescence or adulthood, they usually involve muscle pain and the breakdown of muscle tissue (rhabdomyolysis). The destruction of muscle tissue releases a protein called myoglobin, which is processed by the kidneys and released in the urine (myoglobinuria). Myoglobin causes the urine to be red or brown. In both children and adults, problems related to VLCAD deficiency can be triggered by periods of fasting, illness, and exercise. In affected children, this disorder is sometimes mistaken for Reye syndrome, a severe disorder that may develop in children while they appear to be recovering from viral infections such as chicken pox or flu. Most cases of Reye syndrome are associated with the use of aspirin during these viral infections. VLCAD deficiency is estimated to affect 1 in 40,000 to 120,000 people. Variants (also known as mutations) in the ACADVL gene cause VLCAD deficiency. This gene provides instructions for making an enzyme called very long-chain acyl-CoA dehydrogenase, which is required to break down (metabolize) a group of fats called very long-chain fatty acids. These fatty acids are found in foods and the body's fat tissues. Fatty acids are a major source of energy for the heart and muscles. During periods of fasting, fatty acids are also an important energy source for the liver and other tissues. Variants in the ACADVL gene lead to a shortage (deficiency) of the VLCAD enzyme within cells. Without sufficient amounts of this enzyme, very long-chain fatty acids are not broken down properly. As a result, these fats are not converted to energy, which can lead to the characteristic signs and symptoms of this disorder such as lethargy and hypoglycemia. Very long-chain fatty acids or partially metabolized fatty acids may also build up in tissues and damage the heart, liver, and muscles. This abnormal buildup causes the other signs and symptoms of VLCAD deficiency. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have variants. The parents of an individual with an autosomal recessive condition each carry one copy of the altered gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) very long-chain acyl-CoA dehydrogenase deficiency ? | Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is a condition that prevents the body from converting certain fats to energy, particularly during periods without food (fasting). Signs and symptoms of VLCAD deficiency typically appear during infancy or early childhood and can include low blood sugar (hypoglycemia), lack of energy (lethargy), and muscle weakness. Affected individuals are also at risk for serious complications such as liver abnormalities and life-threatening heart problems. When symptoms begin in adolescence or adulthood, they tend to be milder and usually do not involve the heart. Problems related to VLCAD deficiency can be triggered by periods of fasting, illness, and exercise. This disorder is sometimes mistaken for Reye syndrome, a severe disorder that may develop in children while they appear to be recovering from viral infections such as chicken pox or flu. Most cases of Reye syndrome are associated with the use of aspirin during these viral infections. |
Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is a condition that prevents the body from converting certain fats to energy, particularly during periods without food (fasting). Signs and symptoms of VLCAD deficiency typically appear during infancy or early childhood and can include low blood sugar (hypoglycemia), lack of energy (lethargy), and muscle weakness. Affected individuals are also at risk for serious complications such as liver abnormalities and life-threatening heart problems. When symptoms begin in adolescence or adulthood, they usually involve muscle pain and the breakdown of muscle tissue (rhabdomyolysis). The destruction of muscle tissue releases a protein called myoglobin, which is processed by the kidneys and released in the urine (myoglobinuria). Myoglobin causes the urine to be red or brown. In both children and adults, problems related to VLCAD deficiency can be triggered by periods of fasting, illness, and exercise. In affected children, this disorder is sometimes mistaken for Reye syndrome, a severe disorder that may develop in children while they appear to be recovering from viral infections such as chicken pox or flu. Most cases of Reye syndrome are associated with the use of aspirin during these viral infections. VLCAD deficiency is estimated to affect 1 in 40,000 to 120,000 people. Variants (also known as mutations) in the ACADVL gene cause VLCAD deficiency. This gene provides instructions for making an enzyme called very long-chain acyl-CoA dehydrogenase, which is required to break down (metabolize) a group of fats called very long-chain fatty acids. These fatty acids are found in foods and the body's fat tissues. Fatty acids are a major source of energy for the heart and muscles. During periods of fasting, fatty acids are also an important energy source for the liver and other tissues. Variants in the ACADVL gene lead to a shortage (deficiency) of the VLCAD enzyme within cells. Without sufficient amounts of this enzyme, very long-chain fatty acids are not broken down properly. As a result, these fats are not converted to energy, which can lead to the characteristic signs and symptoms of this disorder such as lethargy and hypoglycemia. Very long-chain fatty acids or partially metabolized fatty acids may also build up in tissues and damage the heart, liver, and muscles. This abnormal buildup causes the other signs and symptoms of VLCAD deficiency. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have variants. The parents of an individual with an autosomal recessive condition each carry one copy of the altered gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by very long-chain acyl-CoA dehydrogenase deficiency ? | VLCAD deficiency is estimated to affect 1 in 40,000 to 120,000 people. |
Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is a condition that prevents the body from converting certain fats to energy, particularly during periods without food (fasting). Signs and symptoms of VLCAD deficiency typically appear during infancy or early childhood and can include low blood sugar (hypoglycemia), lack of energy (lethargy), and muscle weakness. Affected individuals are also at risk for serious complications such as liver abnormalities and life-threatening heart problems. When symptoms begin in adolescence or adulthood, they usually involve muscle pain and the breakdown of muscle tissue (rhabdomyolysis). The destruction of muscle tissue releases a protein called myoglobin, which is processed by the kidneys and released in the urine (myoglobinuria). Myoglobin causes the urine to be red or brown. In both children and adults, problems related to VLCAD deficiency can be triggered by periods of fasting, illness, and exercise. In affected children, this disorder is sometimes mistaken for Reye syndrome, a severe disorder that may develop in children while they appear to be recovering from viral infections such as chicken pox or flu. Most cases of Reye syndrome are associated with the use of aspirin during these viral infections. VLCAD deficiency is estimated to affect 1 in 40,000 to 120,000 people. Variants (also known as mutations) in the ACADVL gene cause VLCAD deficiency. This gene provides instructions for making an enzyme called very long-chain acyl-CoA dehydrogenase, which is required to break down (metabolize) a group of fats called very long-chain fatty acids. These fatty acids are found in foods and the body's fat tissues. Fatty acids are a major source of energy for the heart and muscles. During periods of fasting, fatty acids are also an important energy source for the liver and other tissues. Variants in the ACADVL gene lead to a shortage (deficiency) of the VLCAD enzyme within cells. Without sufficient amounts of this enzyme, very long-chain fatty acids are not broken down properly. As a result, these fats are not converted to energy, which can lead to the characteristic signs and symptoms of this disorder such as lethargy and hypoglycemia. Very long-chain fatty acids or partially metabolized fatty acids may also build up in tissues and damage the heart, liver, and muscles. This abnormal buildup causes the other signs and symptoms of VLCAD deficiency. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have variants. The parents of an individual with an autosomal recessive condition each carry one copy of the altered gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to very long-chain acyl-CoA dehydrogenase deficiency ? | Mutations in the ACADVL gene cause VLCAD deficiency. This gene provides instructions for making an enzyme called very long-chain acyl-CoA dehydrogenase, which is required to break down (metabolize) a group of fats called very long-chain fatty acids. These fatty acids are found in foods and the body's fat tissues. Fatty acids are a major source of energy for the heart and muscles. During periods of fasting, fatty acids are also an important energy source for the liver and other tissues. Mutations in the ACADVL gene lead to a shortage (deficiency) of the VLCAD enzyme within cells. Without sufficient amounts of this enzyme, very long-chain fatty acids are not metabolized properly. As a result, these fats are not converted to energy, which can lead to the characteristic signs and symptoms of this disorder such as lethargy and hypoglycemia. Very long-chain fatty acids or partially metabolized fatty acids may also build up in tissues and damage the heart, liver, and muscles. This abnormal buildup causes the other signs and symptoms of VLCAD deficiency. |
Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is a condition that prevents the body from converting certain fats to energy, particularly during periods without food (fasting). Signs and symptoms of VLCAD deficiency typically appear during infancy or early childhood and can include low blood sugar (hypoglycemia), lack of energy (lethargy), and muscle weakness. Affected individuals are also at risk for serious complications such as liver abnormalities and life-threatening heart problems. When symptoms begin in adolescence or adulthood, they usually involve muscle pain and the breakdown of muscle tissue (rhabdomyolysis). The destruction of muscle tissue releases a protein called myoglobin, which is processed by the kidneys and released in the urine (myoglobinuria). Myoglobin causes the urine to be red or brown. In both children and adults, problems related to VLCAD deficiency can be triggered by periods of fasting, illness, and exercise. In affected children, this disorder is sometimes mistaken for Reye syndrome, a severe disorder that may develop in children while they appear to be recovering from viral infections such as chicken pox or flu. Most cases of Reye syndrome are associated with the use of aspirin during these viral infections. VLCAD deficiency is estimated to affect 1 in 40,000 to 120,000 people. Variants (also known as mutations) in the ACADVL gene cause VLCAD deficiency. This gene provides instructions for making an enzyme called very long-chain acyl-CoA dehydrogenase, which is required to break down (metabolize) a group of fats called very long-chain fatty acids. These fatty acids are found in foods and the body's fat tissues. Fatty acids are a major source of energy for the heart and muscles. During periods of fasting, fatty acids are also an important energy source for the liver and other tissues. Variants in the ACADVL gene lead to a shortage (deficiency) of the VLCAD enzyme within cells. Without sufficient amounts of this enzyme, very long-chain fatty acids are not broken down properly. As a result, these fats are not converted to energy, which can lead to the characteristic signs and symptoms of this disorder such as lethargy and hypoglycemia. Very long-chain fatty acids or partially metabolized fatty acids may also build up in tissues and damage the heart, liver, and muscles. This abnormal buildup causes the other signs and symptoms of VLCAD deficiency. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have variants. The parents of an individual with an autosomal recessive condition each carry one copy of the altered gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is very long-chain acyl-CoA dehydrogenase deficiency inherited ? | This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. |
Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is a condition that prevents the body from converting certain fats to energy, particularly during periods without food (fasting). Signs and symptoms of VLCAD deficiency typically appear during infancy or early childhood and can include low blood sugar (hypoglycemia), lack of energy (lethargy), and muscle weakness. Affected individuals are also at risk for serious complications such as liver abnormalities and life-threatening heart problems. When symptoms begin in adolescence or adulthood, they usually involve muscle pain and the breakdown of muscle tissue (rhabdomyolysis). The destruction of muscle tissue releases a protein called myoglobin, which is processed by the kidneys and released in the urine (myoglobinuria). Myoglobin causes the urine to be red or brown. In both children and adults, problems related to VLCAD deficiency can be triggered by periods of fasting, illness, and exercise. In affected children, this disorder is sometimes mistaken for Reye syndrome, a severe disorder that may develop in children while they appear to be recovering from viral infections such as chicken pox or flu. Most cases of Reye syndrome are associated with the use of aspirin during these viral infections. VLCAD deficiency is estimated to affect 1 in 40,000 to 120,000 people. Variants (also known as mutations) in the ACADVL gene cause VLCAD deficiency. This gene provides instructions for making an enzyme called very long-chain acyl-CoA dehydrogenase, which is required to break down (metabolize) a group of fats called very long-chain fatty acids. These fatty acids are found in foods and the body's fat tissues. Fatty acids are a major source of energy for the heart and muscles. During periods of fasting, fatty acids are also an important energy source for the liver and other tissues. Variants in the ACADVL gene lead to a shortage (deficiency) of the VLCAD enzyme within cells. Without sufficient amounts of this enzyme, very long-chain fatty acids are not broken down properly. As a result, these fats are not converted to energy, which can lead to the characteristic signs and symptoms of this disorder such as lethargy and hypoglycemia. Very long-chain fatty acids or partially metabolized fatty acids may also build up in tissues and damage the heart, liver, and muscles. This abnormal buildup causes the other signs and symptoms of VLCAD deficiency. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have variants. The parents of an individual with an autosomal recessive condition each carry one copy of the altered gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for very long-chain acyl-CoA dehydrogenase deficiency ? | These resources address the diagnosis or management of VLCAD deficiency: - Baby's First Test - Gene Review: Gene Review: Very Long-Chain Acyl-Coenzyme A Dehydrogenase Deficiency - Genetic Testing Registry: Very long chain acyl-CoA dehydrogenase deficiency - MedlinePlus Encyclopedia: Newborn Screening Tests These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
CHST3-related skeletal dysplasia is a genetic condition characterized by bone and joint abnormalities that worsen over time. Affected individuals have short stature throughout life, with an adult height under 4 and a half feet. Joint dislocations, most often affecting the knees, hips, and elbows, are present at birth (congenital). Other bone and joint abnormalities can include an inward- and upward-turning foot (clubfoot), a limited range of motion in large joints, and abnormal curvature of the spine. The features of CHST3-related skeletal dysplasia are usually limited to the bones and joints; however, minor heart defects have been reported in a few affected individuals. Researchers have not settled on a preferred name for this condition. It is sometimes known as autosomal recessive Larsen syndrome based on its similarity to another skeletal disorder called Larsen syndrome. Other names that have been used to describe the condition include spondyloepiphyseal dysplasia, Omani type; humero-spinal dysostosis; and chondrodysplasia with multiple dislocations. Recently, researchers have proposed the umbrella term CHST3-related skeletal dysplasia to refer to bone and joint abnormalities resulting from mutations in the CHST3 gene. The prevalence of CHST3-related skeletal dysplasia is unknown. More than 30 affected individuals have been reported. As its name suggests, CHST3-related skeletal dysplasia results from mutations in the CHST3 gene. This gene provides instructions for making an enzyme called C6ST-1, which is essential for the normal development of cartilage. Cartilage is a tough, flexible tissue that makes up much of the skeleton during early development. Most cartilage is later converted to bone, except for the cartilage that continues to cover and protect the ends of bones and is present in the nose and external ears. Mutations in the CHST3 gene reduce or eliminate the activity of the C6ST-1 enzyme. A shortage of this enzyme disrupts the normal development of cartilage and bone, resulting in the abnormalities associated with CHST3-related skeletal dysplasia. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) CHST3-related skeletal dysplasia ? | CHST3-related skeletal dysplasia is a genetic condition characterized by bone and joint abnormalities that worsen over time. Affected individuals have short stature throughout life, with an adult height under 4 and a half feet. Joint dislocations, most often affecting the knees, hips, and elbows, are present at birth (congenital). Other bone and joint abnormalities can include an inward- and upward-turning foot (clubfoot), a limited range of motion in large joints, and abnormal curvature of the spine. The features of CHST3-related skeletal dysplasia are usually limited to the bones and joints; however, minor heart defects have been reported in a few affected individuals. Researchers have not settled on a preferred name for this condition. It is sometimes known as autosomal recessive Larsen syndrome based on its similarity to another skeletal disorder called Larsen syndrome. Other names that have been used to describe the condition include spondyloepiphyseal dysplasia, Omani type; humero-spinal dysostosis; and chondrodysplasia with multiple dislocations. Recently, researchers have proposed the umbrella term CHST3-related skeletal dysplasia to refer to bone and joint abnormalities resulting from mutations in the CHST3 gene. |
CHST3-related skeletal dysplasia is a genetic condition characterized by bone and joint abnormalities that worsen over time. Affected individuals have short stature throughout life, with an adult height under 4 and a half feet. Joint dislocations, most often affecting the knees, hips, and elbows, are present at birth (congenital). Other bone and joint abnormalities can include an inward- and upward-turning foot (clubfoot), a limited range of motion in large joints, and abnormal curvature of the spine. The features of CHST3-related skeletal dysplasia are usually limited to the bones and joints; however, minor heart defects have been reported in a few affected individuals. Researchers have not settled on a preferred name for this condition. It is sometimes known as autosomal recessive Larsen syndrome based on its similarity to another skeletal disorder called Larsen syndrome. Other names that have been used to describe the condition include spondyloepiphyseal dysplasia, Omani type; humero-spinal dysostosis; and chondrodysplasia with multiple dislocations. Recently, researchers have proposed the umbrella term CHST3-related skeletal dysplasia to refer to bone and joint abnormalities resulting from mutations in the CHST3 gene. The prevalence of CHST3-related skeletal dysplasia is unknown. More than 30 affected individuals have been reported. As its name suggests, CHST3-related skeletal dysplasia results from mutations in the CHST3 gene. This gene provides instructions for making an enzyme called C6ST-1, which is essential for the normal development of cartilage. Cartilage is a tough, flexible tissue that makes up much of the skeleton during early development. Most cartilage is later converted to bone, except for the cartilage that continues to cover and protect the ends of bones and is present in the nose and external ears. Mutations in the CHST3 gene reduce or eliminate the activity of the C6ST-1 enzyme. A shortage of this enzyme disrupts the normal development of cartilage and bone, resulting in the abnormalities associated with CHST3-related skeletal dysplasia. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by CHST3-related skeletal dysplasia ? | The prevalence of CHST3-related skeletal dysplasia is unknown. More than 30 affected individuals have been reported. |
CHST3-related skeletal dysplasia is a genetic condition characterized by bone and joint abnormalities that worsen over time. Affected individuals have short stature throughout life, with an adult height under 4 and a half feet. Joint dislocations, most often affecting the knees, hips, and elbows, are present at birth (congenital). Other bone and joint abnormalities can include an inward- and upward-turning foot (clubfoot), a limited range of motion in large joints, and abnormal curvature of the spine. The features of CHST3-related skeletal dysplasia are usually limited to the bones and joints; however, minor heart defects have been reported in a few affected individuals. Researchers have not settled on a preferred name for this condition. It is sometimes known as autosomal recessive Larsen syndrome based on its similarity to another skeletal disorder called Larsen syndrome. Other names that have been used to describe the condition include spondyloepiphyseal dysplasia, Omani type; humero-spinal dysostosis; and chondrodysplasia with multiple dislocations. Recently, researchers have proposed the umbrella term CHST3-related skeletal dysplasia to refer to bone and joint abnormalities resulting from mutations in the CHST3 gene. The prevalence of CHST3-related skeletal dysplasia is unknown. More than 30 affected individuals have been reported. As its name suggests, CHST3-related skeletal dysplasia results from mutations in the CHST3 gene. This gene provides instructions for making an enzyme called C6ST-1, which is essential for the normal development of cartilage. Cartilage is a tough, flexible tissue that makes up much of the skeleton during early development. Most cartilage is later converted to bone, except for the cartilage that continues to cover and protect the ends of bones and is present in the nose and external ears. Mutations in the CHST3 gene reduce or eliminate the activity of the C6ST-1 enzyme. A shortage of this enzyme disrupts the normal development of cartilage and bone, resulting in the abnormalities associated with CHST3-related skeletal dysplasia. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to CHST3-related skeletal dysplasia ? | As its name suggests, CHST3-related skeletal dysplasia results from mutations in the CHST3 gene. This gene provides instructions for making an enzyme called C6ST-1, which is essential for the normal development of cartilage. Cartilage is a tough, flexible tissue that makes up much of the skeleton during early development. Most cartilage is later converted to bone, except for the cartilage that continues to cover and protect the ends of bones and is present in the nose and external ears. Mutations in the CHST3 gene reduce or eliminate the activity of the C6ST-1 enzyme. A shortage of this enzyme disrupts the normal development of cartilage and bone, resulting in the abnormalities associated with CHST3-related skeletal dysplasia. |
CHST3-related skeletal dysplasia is a genetic condition characterized by bone and joint abnormalities that worsen over time. Affected individuals have short stature throughout life, with an adult height under 4 and a half feet. Joint dislocations, most often affecting the knees, hips, and elbows, are present at birth (congenital). Other bone and joint abnormalities can include an inward- and upward-turning foot (clubfoot), a limited range of motion in large joints, and abnormal curvature of the spine. The features of CHST3-related skeletal dysplasia are usually limited to the bones and joints; however, minor heart defects have been reported in a few affected individuals. Researchers have not settled on a preferred name for this condition. It is sometimes known as autosomal recessive Larsen syndrome based on its similarity to another skeletal disorder called Larsen syndrome. Other names that have been used to describe the condition include spondyloepiphyseal dysplasia, Omani type; humero-spinal dysostosis; and chondrodysplasia with multiple dislocations. Recently, researchers have proposed the umbrella term CHST3-related skeletal dysplasia to refer to bone and joint abnormalities resulting from mutations in the CHST3 gene. The prevalence of CHST3-related skeletal dysplasia is unknown. More than 30 affected individuals have been reported. As its name suggests, CHST3-related skeletal dysplasia results from mutations in the CHST3 gene. This gene provides instructions for making an enzyme called C6ST-1, which is essential for the normal development of cartilage. Cartilage is a tough, flexible tissue that makes up much of the skeleton during early development. Most cartilage is later converted to bone, except for the cartilage that continues to cover and protect the ends of bones and is present in the nose and external ears. Mutations in the CHST3 gene reduce or eliminate the activity of the C6ST-1 enzyme. A shortage of this enzyme disrupts the normal development of cartilage and bone, resulting in the abnormalities associated with CHST3-related skeletal dysplasia. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is CHST3-related skeletal dysplasia inherited ? | This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. |
CHST3-related skeletal dysplasia is a genetic condition characterized by bone and joint abnormalities that worsen over time. Affected individuals have short stature throughout life, with an adult height under 4 and a half feet. Joint dislocations, most often affecting the knees, hips, and elbows, are present at birth (congenital). Other bone and joint abnormalities can include an inward- and upward-turning foot (clubfoot), a limited range of motion in large joints, and abnormal curvature of the spine. The features of CHST3-related skeletal dysplasia are usually limited to the bones and joints; however, minor heart defects have been reported in a few affected individuals. Researchers have not settled on a preferred name for this condition. It is sometimes known as autosomal recessive Larsen syndrome based on its similarity to another skeletal disorder called Larsen syndrome. Other names that have been used to describe the condition include spondyloepiphyseal dysplasia, Omani type; humero-spinal dysostosis; and chondrodysplasia with multiple dislocations. Recently, researchers have proposed the umbrella term CHST3-related skeletal dysplasia to refer to bone and joint abnormalities resulting from mutations in the CHST3 gene. The prevalence of CHST3-related skeletal dysplasia is unknown. More than 30 affected individuals have been reported. As its name suggests, CHST3-related skeletal dysplasia results from mutations in the CHST3 gene. This gene provides instructions for making an enzyme called C6ST-1, which is essential for the normal development of cartilage. Cartilage is a tough, flexible tissue that makes up much of the skeleton during early development. Most cartilage is later converted to bone, except for the cartilage that continues to cover and protect the ends of bones and is present in the nose and external ears. Mutations in the CHST3 gene reduce or eliminate the activity of the C6ST-1 enzyme. A shortage of this enzyme disrupts the normal development of cartilage and bone, resulting in the abnormalities associated with CHST3-related skeletal dysplasia. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for CHST3-related skeletal dysplasia ? | These resources address the diagnosis or management of CHST3-related skeletal dysplasia: - Gene Review: Gene Review: CHST3-Related Skeletal Dysplasia - Genetic Testing Registry: Spondyloepiphyseal dysplasia with congenital joint dislocations These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Recombinant 8 syndrome is a condition that involves complex congenital heart abnormalities, urinary tract abnormalities, moderate to severe intellectual disability, abnormal muscle tone, and a distinctive facial appearance. The most common heart abnormalities are known as tetrology of Fallot and conotruncal defects. The characteristic facial features include a wide, square face; a thin upper lip; a downturned mouth; a small chin (micrognathia); wide-set eyes (hypertelorism); and low-set or unusually shaped ears.  People with recombinant 8 syndrome may have overgrowth of the gums (gingival hyperplasia), abnormal tooth development, or an opening in the upper lip (cleft lip) with or without an opening in the roof of the mouth (cleft palate). Males with this condition frequently have undescended testes (cryptorchidism). Some affected individuals have recurrent ear infections (otitis media), hearing loss, or hand and finger differences. In individuals with recombinant 8 syndrome, the heart abnormalities can be life-threatening. Recombinant 8 syndrome is a rare condition; its exact incidence is unknown. Most people with this condition are of Hispanic ancestry, particularly from the San Luis Valley area of southern Colorado and northern New Mexico. Recombinant 8 syndrome is also called San Luis Valley syndrome. Only a few cases outside this population have been found. Recombinant 8 syndrome is caused by a rearrangement of chromosome 8 that results in a deletion of a piece of the short (p) arm and a duplication of a piece of the long (q) arm.  The deletion and duplication result in the recombinant 8 chromosome.  On the recombinant 8 chromosome, there is one copy of each of the genes instead of the usual two on the section of chromosome 8p that is deleted; and there are three copies each of the genes on the section of chromosome 8q that is duplicated. The signs and symptoms of recombinant 8 syndrome are related to the loss and addition of genetic material on these regions of chromosome 8.  While the regions affected in recombinant chromosome 8 includes hundreds of genes, researchers are working to determine which genes play a role in the signs and symptoms of this condition. Recombinant 8 syndrome
is inherited in an autosomal dominant pattern, which means one copy of the recombinant chromosome 8 in each cell is sufficient to cause the disorder. Most people with recombinant 8 syndrome have one parent with a change in chromosome 8 called an inversion.  An inversion involves the breakage of a chromosome in two places; the resulting piece of DNA is reversed and reinserted into the chromosome. Genetic material is typically not lost as a result of this inversion in chromosome 8, so people usually do not have any related health problems.  However, genetic material can be lost or duplicated when inversions are passed to the next generation.  People with the chromosome 8 inversion are at of risk having a child with recombinant 8 syndrome. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) recombinant 8 syndrome ? | Recombinant 8 syndrome is a condition that involves heart and urinary tract abnormalities, moderate to severe intellectual disability, and a distinctive facial appearance. The characteristic facial features include a wide, square face; a thin upper lip; a downturned mouth; a small chin (micrognathia); wide-set eyes (hypertelorism); and low-set or unusually shaped ears. People with recombinant 8 syndrome may have overgrowth of the gums (gingival hyperplasia) and abnormal tooth development. Males with this condition frequently have undescended testes (cryptorchidism). Some affected individuals have recurrent ear infections (otitis media) or hearing loss. Many children with recombinant 8 syndrome do not survive past early childhood, usually due to complications related to their heart abnormalities. |
Recombinant 8 syndrome is a condition that involves complex congenital heart abnormalities, urinary tract abnormalities, moderate to severe intellectual disability, abnormal muscle tone, and a distinctive facial appearance. The most common heart abnormalities are known as tetrology of Fallot and conotruncal defects. The characteristic facial features include a wide, square face; a thin upper lip; a downturned mouth; a small chin (micrognathia); wide-set eyes (hypertelorism); and low-set or unusually shaped ears.  People with recombinant 8 syndrome may have overgrowth of the gums (gingival hyperplasia), abnormal tooth development, or an opening in the upper lip (cleft lip) with or without an opening in the roof of the mouth (cleft palate). Males with this condition frequently have undescended testes (cryptorchidism). Some affected individuals have recurrent ear infections (otitis media), hearing loss, or hand and finger differences. In individuals with recombinant 8 syndrome, the heart abnormalities can be life-threatening. Recombinant 8 syndrome is a rare condition; its exact incidence is unknown. Most people with this condition are of Hispanic ancestry, particularly from the San Luis Valley area of southern Colorado and northern New Mexico. Recombinant 8 syndrome is also called San Luis Valley syndrome. Only a few cases outside this population have been found. Recombinant 8 syndrome is caused by a rearrangement of chromosome 8 that results in a deletion of a piece of the short (p) arm and a duplication of a piece of the long (q) arm.  The deletion and duplication result in the recombinant 8 chromosome.  On the recombinant 8 chromosome, there is one copy of each of the genes instead of the usual two on the section of chromosome 8p that is deleted; and there are three copies each of the genes on the section of chromosome 8q that is duplicated. The signs and symptoms of recombinant 8 syndrome are related to the loss and addition of genetic material on these regions of chromosome 8.  While the regions affected in recombinant chromosome 8 includes hundreds of genes, researchers are working to determine which genes play a role in the signs and symptoms of this condition. Recombinant 8 syndrome
is inherited in an autosomal dominant pattern, which means one copy of the recombinant chromosome 8 in each cell is sufficient to cause the disorder. Most people with recombinant 8 syndrome have one parent with a change in chromosome 8 called an inversion.  An inversion involves the breakage of a chromosome in two places; the resulting piece of DNA is reversed and reinserted into the chromosome. Genetic material is typically not lost as a result of this inversion in chromosome 8, so people usually do not have any related health problems.  However, genetic material can be lost or duplicated when inversions are passed to the next generation.  People with the chromosome 8 inversion are at of risk having a child with recombinant 8 syndrome. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by recombinant 8 syndrome ? | Recombinant 8 syndrome is a rare condition; its exact incidence is unknown. Most people with this condition are descended from a Hispanic population originating in the San Luis Valley area of southern Colorado and northern New Mexico. Recombinant 8 syndrome is also called San Luis Valley syndrome. Only a few cases outside this population have been found. |
Recombinant 8 syndrome is a condition that involves complex congenital heart abnormalities, urinary tract abnormalities, moderate to severe intellectual disability, abnormal muscle tone, and a distinctive facial appearance. The most common heart abnormalities are known as tetrology of Fallot and conotruncal defects. The characteristic facial features include a wide, square face; a thin upper lip; a downturned mouth; a small chin (micrognathia); wide-set eyes (hypertelorism); and low-set or unusually shaped ears.  People with recombinant 8 syndrome may have overgrowth of the gums (gingival hyperplasia), abnormal tooth development, or an opening in the upper lip (cleft lip) with or without an opening in the roof of the mouth (cleft palate). Males with this condition frequently have undescended testes (cryptorchidism). Some affected individuals have recurrent ear infections (otitis media), hearing loss, or hand and finger differences. In individuals with recombinant 8 syndrome, the heart abnormalities can be life-threatening. Recombinant 8 syndrome is a rare condition; its exact incidence is unknown. Most people with this condition are of Hispanic ancestry, particularly from the San Luis Valley area of southern Colorado and northern New Mexico. Recombinant 8 syndrome is also called San Luis Valley syndrome. Only a few cases outside this population have been found. Recombinant 8 syndrome is caused by a rearrangement of chromosome 8 that results in a deletion of a piece of the short (p) arm and a duplication of a piece of the long (q) arm.  The deletion and duplication result in the recombinant 8 chromosome.  On the recombinant 8 chromosome, there is one copy of each of the genes instead of the usual two on the section of chromosome 8p that is deleted; and there are three copies each of the genes on the section of chromosome 8q that is duplicated. The signs and symptoms of recombinant 8 syndrome are related to the loss and addition of genetic material on these regions of chromosome 8.  While the regions affected in recombinant chromosome 8 includes hundreds of genes, researchers are working to determine which genes play a role in the signs and symptoms of this condition. Recombinant 8 syndrome
is inherited in an autosomal dominant pattern, which means one copy of the recombinant chromosome 8 in each cell is sufficient to cause the disorder. Most people with recombinant 8 syndrome have one parent with a change in chromosome 8 called an inversion.  An inversion involves the breakage of a chromosome in two places; the resulting piece of DNA is reversed and reinserted into the chromosome. Genetic material is typically not lost as a result of this inversion in chromosome 8, so people usually do not have any related health problems.  However, genetic material can be lost or duplicated when inversions are passed to the next generation.  People with the chromosome 8 inversion are at of risk having a child with recombinant 8 syndrome. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to recombinant 8 syndrome ? | Recombinant 8 syndrome is caused by a rearrangement of chromosome 8 that results in a deletion of a piece of the short (p) arm and a duplication of a piece of the long (q) arm. The deletion and duplication result in the recombinant 8 chromosome. The signs and symptoms of recombinant 8 syndrome are related to the loss and addition of genetic material on these regions of chromosome 8. Researchers are working to determine which genes are involved in the deletion and duplication on chromosome 8. |
Recombinant 8 syndrome is a condition that involves complex congenital heart abnormalities, urinary tract abnormalities, moderate to severe intellectual disability, abnormal muscle tone, and a distinctive facial appearance. The most common heart abnormalities are known as tetrology of Fallot and conotruncal defects. The characteristic facial features include a wide, square face; a thin upper lip; a downturned mouth; a small chin (micrognathia); wide-set eyes (hypertelorism); and low-set or unusually shaped ears.  People with recombinant 8 syndrome may have overgrowth of the gums (gingival hyperplasia), abnormal tooth development, or an opening in the upper lip (cleft lip) with or without an opening in the roof of the mouth (cleft palate). Males with this condition frequently have undescended testes (cryptorchidism). Some affected individuals have recurrent ear infections (otitis media), hearing loss, or hand and finger differences. In individuals with recombinant 8 syndrome, the heart abnormalities can be life-threatening. Recombinant 8 syndrome is a rare condition; its exact incidence is unknown. Most people with this condition are of Hispanic ancestry, particularly from the San Luis Valley area of southern Colorado and northern New Mexico. Recombinant 8 syndrome is also called San Luis Valley syndrome. Only a few cases outside this population have been found. Recombinant 8 syndrome is caused by a rearrangement of chromosome 8 that results in a deletion of a piece of the short (p) arm and a duplication of a piece of the long (q) arm.  The deletion and duplication result in the recombinant 8 chromosome.  On the recombinant 8 chromosome, there is one copy of each of the genes instead of the usual two on the section of chromosome 8p that is deleted; and there are three copies each of the genes on the section of chromosome 8q that is duplicated. The signs and symptoms of recombinant 8 syndrome are related to the loss and addition of genetic material on these regions of chromosome 8.  While the regions affected in recombinant chromosome 8 includes hundreds of genes, researchers are working to determine which genes play a role in the signs and symptoms of this condition. Recombinant 8 syndrome
is inherited in an autosomal dominant pattern, which means one copy of the recombinant chromosome 8 in each cell is sufficient to cause the disorder. Most people with recombinant 8 syndrome have one parent with a change in chromosome 8 called an inversion.  An inversion involves the breakage of a chromosome in two places; the resulting piece of DNA is reversed and reinserted into the chromosome. Genetic material is typically not lost as a result of this inversion in chromosome 8, so people usually do not have any related health problems.  However, genetic material can be lost or duplicated when inversions are passed to the next generation.  People with the chromosome 8 inversion are at of risk having a child with recombinant 8 syndrome. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is recombinant 8 syndrome inherited ? | This condition is inherited in an autosomal dominant pattern, which means one copy of the recombinant chromosome 8 in each cell is sufficient to cause the disorder. Most people with recombinant 8 syndrome have at least one parent with a change in chromosome 8 called an inversion. An inversion involves the breakage of a chromosome in two places; the resulting piece of DNA is reversed and reinserted into the chromosome. Genetic material is typically not lost as a result of this inversion in chromosome 8, so people usually do not have any related health problems. However, genetic material can be lost or duplicated when inversions are being passed to the next generation. People with this chromosome 8 inversion are at of risk having a child with recombinant 8 syndrome. |
Recombinant 8 syndrome is a condition that involves complex congenital heart abnormalities, urinary tract abnormalities, moderate to severe intellectual disability, abnormal muscle tone, and a distinctive facial appearance. The most common heart abnormalities are known as tetrology of Fallot and conotruncal defects. The characteristic facial features include a wide, square face; a thin upper lip; a downturned mouth; a small chin (micrognathia); wide-set eyes (hypertelorism); and low-set or unusually shaped ears.  People with recombinant 8 syndrome may have overgrowth of the gums (gingival hyperplasia), abnormal tooth development, or an opening in the upper lip (cleft lip) with or without an opening in the roof of the mouth (cleft palate). Males with this condition frequently have undescended testes (cryptorchidism). Some affected individuals have recurrent ear infections (otitis media), hearing loss, or hand and finger differences. In individuals with recombinant 8 syndrome, the heart abnormalities can be life-threatening. Recombinant 8 syndrome is a rare condition; its exact incidence is unknown. Most people with this condition are of Hispanic ancestry, particularly from the San Luis Valley area of southern Colorado and northern New Mexico. Recombinant 8 syndrome is also called San Luis Valley syndrome. Only a few cases outside this population have been found. Recombinant 8 syndrome is caused by a rearrangement of chromosome 8 that results in a deletion of a piece of the short (p) arm and a duplication of a piece of the long (q) arm.  The deletion and duplication result in the recombinant 8 chromosome.  On the recombinant 8 chromosome, there is one copy of each of the genes instead of the usual two on the section of chromosome 8p that is deleted; and there are three copies each of the genes on the section of chromosome 8q that is duplicated. The signs and symptoms of recombinant 8 syndrome are related to the loss and addition of genetic material on these regions of chromosome 8.  While the regions affected in recombinant chromosome 8 includes hundreds of genes, researchers are working to determine which genes play a role in the signs and symptoms of this condition. Recombinant 8 syndrome
is inherited in an autosomal dominant pattern, which means one copy of the recombinant chromosome 8 in each cell is sufficient to cause the disorder. Most people with recombinant 8 syndrome have one parent with a change in chromosome 8 called an inversion.  An inversion involves the breakage of a chromosome in two places; the resulting piece of DNA is reversed and reinserted into the chromosome. Genetic material is typically not lost as a result of this inversion in chromosome 8, so people usually do not have any related health problems.  However, genetic material can be lost or duplicated when inversions are passed to the next generation.  People with the chromosome 8 inversion are at of risk having a child with recombinant 8 syndrome. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for recombinant 8 syndrome ? | These resources address the diagnosis or management of recombinant 8 syndrome: - Genetic Testing Registry: Recombinant chromosome 8 syndrome These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Autosomal recessive spastic ataxia of Charlevoix-Saguenay, more commonly known as ARSACS, is a condition affecting muscle movement. People with ARSACS typically have abnormal tensing of the muscles (spasticity), problems with balance and coordination (cerebellar ataxia), and reduced sensation and weakness in the arms and legs (peripheral neuropathy). Additional muscle problems that can occur in ARSACS include muscle wasting (amyotrophy), involuntary eye movements (nystagmus), and difficulty swallowing (dysphagia) and speaking (dysarthria). Other features of ARSACS involve high-arched feet (pes cavus), a spine that curves to the side (scoliosis), yellow streaks of fatty tissue in the light-sensitive tissue at the back of the eye (hypermyelination of the retina), urinary tract problems, intellectual disability, hearing loss, and recurrent seizures (epilepsy). An unsteady walking style (gait) is the first symptom of ARSACS. Walking problems usually begin between the ages of 12 months and 18 months, as toddlers are learning to walk. These movement problems worsen over time, with increased spasticity and ataxia of the arms and legs. In some cases spasticity goes away, but this apparent improvement is thought to be due to the wasting away (atrophy) of nerves in the arms and legs. Most affected individuals require wheelchair assistance by the time they are in their thirties or forties. While this condition was named after the area in which it was first seen, the Charlevoix-Saguenay region of Quebec, Canada, ARSACS has been identified in individuals worldwide. The incidence of ARSACS in the Charlevoix-Saguenay region is estimated to be 1 in 1,500 to 2,000 individuals. Outside of Quebec, the incidence of ARSACS is unknown. About 200 individuals with ARSACS have been described in the scientific literature. Mutations in the SACS gene cause ARSACS. The SACS gene provides instructions for producing a protein called sacsin. Sacsin is primarily found in cells in the brain, skin, and muscles used for movement (skeletal muscles), but the specific function of the protein is unknown. Research suggests that sacsin plays a role in organizing proteins into bundles called intermediate filaments. Intermediate filaments provide support and strength to cells. In nerve cells (neurons), specialized intermediate filaments called neurofilaments comprise the structural framework that establishes the size and shape of nerve cell extensions called axons, which are essential for transmission of nerve impulses to other neurons and to muscle cells. Mutations in the SACS gene cause the production of an unstable sacsin protein that does not function normally. It is unclear how the abnormal sacsin protein affects the brain and skeletal muscles but it likely impairs normal organization of intermediate filaments in cells, particularly neurofilaments, and disrupts neuron function. This decreased neuronal signaling may result in the signs and symptoms of ARSACS. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) autosomal recessive spastic ataxia of Charlevoix-Saguenay ? | Autosomal recessive spastic ataxia of Charlevoix-Saguenay, more commonly known as ARSACS, is a condition affecting muscle movement. People with ARSACS typically have abnormal tensing of the muscles (spasticity), difficulty coordinating movements (ataxia), muscle wasting (amyotrophy), involuntary eye movements (nystagmus), and speech difficulties (dysarthria). Other problems may include deformities of the fingers and feet, reduced sensation and weakness in the arms and legs (peripheral neuropathy), yellow streaks of fatty tissue in the light-sensitive tissue at the back of the eye (hypermyelination of the retina), and less commonly, leaks in one of the valves that control blood flow through the heart (mitral valve prolapse). An unsteady gait is the first symptom of ARSACS. It usually appears between the age of 12 months and 18 months, as toddlers are learning to walk. The signs and symptoms worsen over the years, with increased spasticity and ataxia of the arms and legs. In some cases spasticity disappears, but this apparent improvement is thought to be due to degeneration of nerves in the arms and legs. Most affected individuals require a wheelchair by the time they are in their thirties or forties. This condition was first seen in people of the Charlevoix-Saguenay region of Quebec, Canada. The majority of people with ARSACS live in Quebec or have recent ancestors from Quebec. People with ARSACS have also been identified in Japan, Turkey, Tunisia, Spain, Italy, and Belgium. The signs and symptoms of ARSACS seen in other countries differ from those in Quebec. In people with ARSACS outside of Quebec, hypermyelination of the retina is seen less often, intelligence may be below normal, and symptoms tend to appear at a later age. |
Autosomal recessive spastic ataxia of Charlevoix-Saguenay, more commonly known as ARSACS, is a condition affecting muscle movement. People with ARSACS typically have abnormal tensing of the muscles (spasticity), problems with balance and coordination (cerebellar ataxia), and reduced sensation and weakness in the arms and legs (peripheral neuropathy). Additional muscle problems that can occur in ARSACS include muscle wasting (amyotrophy), involuntary eye movements (nystagmus), and difficulty swallowing (dysphagia) and speaking (dysarthria). Other features of ARSACS involve high-arched feet (pes cavus), a spine that curves to the side (scoliosis), yellow streaks of fatty tissue in the light-sensitive tissue at the back of the eye (hypermyelination of the retina), urinary tract problems, intellectual disability, hearing loss, and recurrent seizures (epilepsy). An unsteady walking style (gait) is the first symptom of ARSACS. Walking problems usually begin between the ages of 12 months and 18 months, as toddlers are learning to walk. These movement problems worsen over time, with increased spasticity and ataxia of the arms and legs. In some cases spasticity goes away, but this apparent improvement is thought to be due to the wasting away (atrophy) of nerves in the arms and legs. Most affected individuals require wheelchair assistance by the time they are in their thirties or forties. While this condition was named after the area in which it was first seen, the Charlevoix-Saguenay region of Quebec, Canada, ARSACS has been identified in individuals worldwide. The incidence of ARSACS in the Charlevoix-Saguenay region is estimated to be 1 in 1,500 to 2,000 individuals. Outside of Quebec, the incidence of ARSACS is unknown. About 200 individuals with ARSACS have been described in the scientific literature. Mutations in the SACS gene cause ARSACS. The SACS gene provides instructions for producing a protein called sacsin. Sacsin is primarily found in cells in the brain, skin, and muscles used for movement (skeletal muscles), but the specific function of the protein is unknown. Research suggests that sacsin plays a role in organizing proteins into bundles called intermediate filaments. Intermediate filaments provide support and strength to cells. In nerve cells (neurons), specialized intermediate filaments called neurofilaments comprise the structural framework that establishes the size and shape of nerve cell extensions called axons, which are essential for transmission of nerve impulses to other neurons and to muscle cells. Mutations in the SACS gene cause the production of an unstable sacsin protein that does not function normally. It is unclear how the abnormal sacsin protein affects the brain and skeletal muscles but it likely impairs normal organization of intermediate filaments in cells, particularly neurofilaments, and disrupts neuron function. This decreased neuronal signaling may result in the signs and symptoms of ARSACS. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by autosomal recessive spastic ataxia of Charlevoix-Saguenay ? | The incidence of ARSACS in the Charlevoix-Saguenay region of Quebec is estimated to be 1 in 1,500 to 2,000 individuals. Outside of Quebec, ARSACS is rare, but the incidence is unknown. |
Autosomal recessive spastic ataxia of Charlevoix-Saguenay, more commonly known as ARSACS, is a condition affecting muscle movement. People with ARSACS typically have abnormal tensing of the muscles (spasticity), problems with balance and coordination (cerebellar ataxia), and reduced sensation and weakness in the arms and legs (peripheral neuropathy). Additional muscle problems that can occur in ARSACS include muscle wasting (amyotrophy), involuntary eye movements (nystagmus), and difficulty swallowing (dysphagia) and speaking (dysarthria). Other features of ARSACS involve high-arched feet (pes cavus), a spine that curves to the side (scoliosis), yellow streaks of fatty tissue in the light-sensitive tissue at the back of the eye (hypermyelination of the retina), urinary tract problems, intellectual disability, hearing loss, and recurrent seizures (epilepsy). An unsteady walking style (gait) is the first symptom of ARSACS. Walking problems usually begin between the ages of 12 months and 18 months, as toddlers are learning to walk. These movement problems worsen over time, with increased spasticity and ataxia of the arms and legs. In some cases spasticity goes away, but this apparent improvement is thought to be due to the wasting away (atrophy) of nerves in the arms and legs. Most affected individuals require wheelchair assistance by the time they are in their thirties or forties. While this condition was named after the area in which it was first seen, the Charlevoix-Saguenay region of Quebec, Canada, ARSACS has been identified in individuals worldwide. The incidence of ARSACS in the Charlevoix-Saguenay region is estimated to be 1 in 1,500 to 2,000 individuals. Outside of Quebec, the incidence of ARSACS is unknown. About 200 individuals with ARSACS have been described in the scientific literature. Mutations in the SACS gene cause ARSACS. The SACS gene provides instructions for producing a protein called sacsin. Sacsin is primarily found in cells in the brain, skin, and muscles used for movement (skeletal muscles), but the specific function of the protein is unknown. Research suggests that sacsin plays a role in organizing proteins into bundles called intermediate filaments. Intermediate filaments provide support and strength to cells. In nerve cells (neurons), specialized intermediate filaments called neurofilaments comprise the structural framework that establishes the size and shape of nerve cell extensions called axons, which are essential for transmission of nerve impulses to other neurons and to muscle cells. Mutations in the SACS gene cause the production of an unstable sacsin protein that does not function normally. It is unclear how the abnormal sacsin protein affects the brain and skeletal muscles but it likely impairs normal organization of intermediate filaments in cells, particularly neurofilaments, and disrupts neuron function. This decreased neuronal signaling may result in the signs and symptoms of ARSACS. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to autosomal recessive spastic ataxia of Charlevoix-Saguenay ? | Mutations in the SACS gene cause ARSACS. The SACS gene provides instructions for producing a protein called sacsin. Sacsin is found in the brain, skin cells, muscles used for movement (skeletal muscles), and at low levels in the pancreas, but the specific function of the protein is unknown. Research suggests that sacsin might play a role in folding newly produced proteins into the proper 3-dimensional shape because it shares similar regions with other proteins that perform this function. Mutations in the SACS gene cause the production of an unstable sacsin protein that does not function normally. It is unclear how the abnormal sacsin protein affects the brain and skeletal muscles and results in the signs and symptoms of ARSACS. |
Autosomal recessive spastic ataxia of Charlevoix-Saguenay, more commonly known as ARSACS, is a condition affecting muscle movement. People with ARSACS typically have abnormal tensing of the muscles (spasticity), problems with balance and coordination (cerebellar ataxia), and reduced sensation and weakness in the arms and legs (peripheral neuropathy). Additional muscle problems that can occur in ARSACS include muscle wasting (amyotrophy), involuntary eye movements (nystagmus), and difficulty swallowing (dysphagia) and speaking (dysarthria). Other features of ARSACS involve high-arched feet (pes cavus), a spine that curves to the side (scoliosis), yellow streaks of fatty tissue in the light-sensitive tissue at the back of the eye (hypermyelination of the retina), urinary tract problems, intellectual disability, hearing loss, and recurrent seizures (epilepsy). An unsteady walking style (gait) is the first symptom of ARSACS. Walking problems usually begin between the ages of 12 months and 18 months, as toddlers are learning to walk. These movement problems worsen over time, with increased spasticity and ataxia of the arms and legs. In some cases spasticity goes away, but this apparent improvement is thought to be due to the wasting away (atrophy) of nerves in the arms and legs. Most affected individuals require wheelchair assistance by the time they are in their thirties or forties. While this condition was named after the area in which it was first seen, the Charlevoix-Saguenay region of Quebec, Canada, ARSACS has been identified in individuals worldwide. The incidence of ARSACS in the Charlevoix-Saguenay region is estimated to be 1 in 1,500 to 2,000 individuals. Outside of Quebec, the incidence of ARSACS is unknown. About 200 individuals with ARSACS have been described in the scientific literature. Mutations in the SACS gene cause ARSACS. The SACS gene provides instructions for producing a protein called sacsin. Sacsin is primarily found in cells in the brain, skin, and muscles used for movement (skeletal muscles), but the specific function of the protein is unknown. Research suggests that sacsin plays a role in organizing proteins into bundles called intermediate filaments. Intermediate filaments provide support and strength to cells. In nerve cells (neurons), specialized intermediate filaments called neurofilaments comprise the structural framework that establishes the size and shape of nerve cell extensions called axons, which are essential for transmission of nerve impulses to other neurons and to muscle cells. Mutations in the SACS gene cause the production of an unstable sacsin protein that does not function normally. It is unclear how the abnormal sacsin protein affects the brain and skeletal muscles but it likely impairs normal organization of intermediate filaments in cells, particularly neurofilaments, and disrupts neuron function. This decreased neuronal signaling may result in the signs and symptoms of ARSACS. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is autosomal recessive spastic ataxia of Charlevoix-Saguenay inherited ? | This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. |
Autosomal recessive spastic ataxia of Charlevoix-Saguenay, more commonly known as ARSACS, is a condition affecting muscle movement. People with ARSACS typically have abnormal tensing of the muscles (spasticity), problems with balance and coordination (cerebellar ataxia), and reduced sensation and weakness in the arms and legs (peripheral neuropathy). Additional muscle problems that can occur in ARSACS include muscle wasting (amyotrophy), involuntary eye movements (nystagmus), and difficulty swallowing (dysphagia) and speaking (dysarthria). Other features of ARSACS involve high-arched feet (pes cavus), a spine that curves to the side (scoliosis), yellow streaks of fatty tissue in the light-sensitive tissue at the back of the eye (hypermyelination of the retina), urinary tract problems, intellectual disability, hearing loss, and recurrent seizures (epilepsy). An unsteady walking style (gait) is the first symptom of ARSACS. Walking problems usually begin between the ages of 12 months and 18 months, as toddlers are learning to walk. These movement problems worsen over time, with increased spasticity and ataxia of the arms and legs. In some cases spasticity goes away, but this apparent improvement is thought to be due to the wasting away (atrophy) of nerves in the arms and legs. Most affected individuals require wheelchair assistance by the time they are in their thirties or forties. While this condition was named after the area in which it was first seen, the Charlevoix-Saguenay region of Quebec, Canada, ARSACS has been identified in individuals worldwide. The incidence of ARSACS in the Charlevoix-Saguenay region is estimated to be 1 in 1,500 to 2,000 individuals. Outside of Quebec, the incidence of ARSACS is unknown. About 200 individuals with ARSACS have been described in the scientific literature. Mutations in the SACS gene cause ARSACS. The SACS gene provides instructions for producing a protein called sacsin. Sacsin is primarily found in cells in the brain, skin, and muscles used for movement (skeletal muscles), but the specific function of the protein is unknown. Research suggests that sacsin plays a role in organizing proteins into bundles called intermediate filaments. Intermediate filaments provide support and strength to cells. In nerve cells (neurons), specialized intermediate filaments called neurofilaments comprise the structural framework that establishes the size and shape of nerve cell extensions called axons, which are essential for transmission of nerve impulses to other neurons and to muscle cells. Mutations in the SACS gene cause the production of an unstable sacsin protein that does not function normally. It is unclear how the abnormal sacsin protein affects the brain and skeletal muscles but it likely impairs normal organization of intermediate filaments in cells, particularly neurofilaments, and disrupts neuron function. This decreased neuronal signaling may result in the signs and symptoms of ARSACS. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for autosomal recessive spastic ataxia of Charlevoix-Saguenay ? | These resources address the diagnosis or management of ARSACS: - Gene Review: Gene Review: ARSACS - Genetic Testing Registry: Spastic ataxia Charlevoix-Saguenay type These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Baller-Gerold syndrome is a rare condition characterized by the premature fusion of certain skull bones (craniosynostosis) and abnormalities of bones in the arms and hands. People with Baller-Gerold syndrome have prematurely fused skull bones, most often along the coronal suture, the growth line that goes over the head from ear to ear. Other sutures of the skull may be fused as well. These changes result in an abnormally shaped head, a prominent forehead, and bulging eyes with shallow eye sockets (ocular proptosis). Other distinctive facial features can include widely spaced eyes (hypertelorism), a small mouth, and a saddle-shaped or underdeveloped nose. Bone abnormalities in the hands include missing fingers (oligodactyly) and malformed or absent thumbs. Partial or complete absence of bones in the forearm is also common. Together, these hand and arm abnormalities are called radial ray malformations. People with Baller-Gerold syndrome may have a variety of additional signs and symptoms including slow growth beginning in infancy, small stature, and malformed or missing kneecaps (patellae). A skin rash often appears on the arms and legs a few months after birth. This rash spreads over time, causing patchy changes in skin coloring, areas of thinning skin (atrophy), and small clusters of blood vessels just under the skin (telangiectases). These chronic skin problems are collectively known as poikiloderma. The varied signs and symptoms of Baller-Gerold syndrome overlap with features of other disorders, namely Rothmund-Thomson syndrome and RAPADILINO syndrome. These syndromes are also characterized by radial ray defects, skeletal abnormalities, and slow growth. All of these conditions can be caused by mutations in the same gene. Based on these similarities, researchers are investigating whether Baller-Gerold syndrome, Rothmund-Thomson syndrome, and RAPADILINO syndrome are separate disorders or part of a single syndrome with overlapping signs and symptoms. The prevalence of Baller-Gerold syndrome is unknown, but this rare condition probably affects fewer than 1 per million people. Fewer than 40 cases have been reported in the medical literature. Mutations in the RECQL4 gene cause some cases of Baller-Gerold syndrome. This gene provides instructions for making one member of a protein family called RecQ helicases. Helicases are enzymes that bind to DNA and temporarily unwind the two spiral strands (double helix) of the DNA molecule. This unwinding is necessary for copying (replicating) DNA in preparation for cell division, and for repairing damaged DNA. The RECQL4 protein helps stabilize genetic information in the body's cells and plays a role in replicating and repairing DNA. Mutations in the RECQL4 gene prevent cells from producing any RECQL4 protein or change the way the protein is pieced together, which disrupts its usual function. A shortage of this protein may prevent normal DNA replication and repair, causing widespread damage to a person's genetic information over time. It is unclear how a loss of this protein's activity leads to the signs and symptoms of Baller-Gerold syndrome. This condition has been associated with prenatal (before birth) exposure to a drug called sodium valproate. This medication is used to treat epilepsy and certain psychiatric disorders. Some infants whose mothers took sodium valproate during pregnancy were born with the characteristic features of Baller-Gerold syndrome, such as an unusual skull shape, distinctive facial features, and abnormalities of the arms and hands. However, it is unclear if exposure to the medication caused the condition. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) Baller-Gerold syndrome ? | Baller-Gerold syndrome is a rare condition characterized by the premature fusion of certain skull bones (craniosynostosis) and abnormalities of bones in the arms and hands. People with Baller-Gerold syndrome have prematurely fused skull bones, most often along the coronal suture, the growth line that goes over the head from ear to ear. Other sutures of the skull may be fused as well. These changes result in an abnormally shaped head, a prominent forehead, and bulging eyes with shallow eye sockets (ocular proptosis). Other distinctive facial features can include widely spaced eyes (hypertelorism), a small mouth, and a saddle-shaped or underdeveloped nose. Bone abnormalities in the hands include missing fingers (oligodactyly) and malformed or absent thumbs. Partial or complete absence of bones in the forearm is also common. Together, these hand and arm abnormalities are called radial ray malformations. People with Baller-Gerold syndrome may have a variety of additional signs and symptoms including slow growth beginning in infancy, small stature, and malformed or missing kneecaps (patellae). A skin rash often appears on the arms and legs a few months after birth. This rash spreads over time, causing patchy changes in skin coloring, areas of thinning skin (atrophy), and small clusters of blood vessels just under the skin (telangiectases). These chronic skin problems are collectively known as poikiloderma. The varied signs and symptoms of Baller-Gerold syndrome overlap with features of other disorders, namely Rothmund-Thomson syndrome and RAPADILINO syndrome. These syndromes are also characterized by radial ray defects, skeletal abnormalities, and slow growth. All of these conditions can be caused by mutations in the same gene. Based on these similarities, researchers are investigating whether Baller-Gerold syndrome, Rothmund-Thomson syndrome, and RAPADILINO syndrome are separate disorders or part of a single syndrome with overlapping signs and symptoms. |
Baller-Gerold syndrome is a rare condition characterized by the premature fusion of certain skull bones (craniosynostosis) and abnormalities of bones in the arms and hands. People with Baller-Gerold syndrome have prematurely fused skull bones, most often along the coronal suture, the growth line that goes over the head from ear to ear. Other sutures of the skull may be fused as well. These changes result in an abnormally shaped head, a prominent forehead, and bulging eyes with shallow eye sockets (ocular proptosis). Other distinctive facial features can include widely spaced eyes (hypertelorism), a small mouth, and a saddle-shaped or underdeveloped nose. Bone abnormalities in the hands include missing fingers (oligodactyly) and malformed or absent thumbs. Partial or complete absence of bones in the forearm is also common. Together, these hand and arm abnormalities are called radial ray malformations. People with Baller-Gerold syndrome may have a variety of additional signs and symptoms including slow growth beginning in infancy, small stature, and malformed or missing kneecaps (patellae). A skin rash often appears on the arms and legs a few months after birth. This rash spreads over time, causing patchy changes in skin coloring, areas of thinning skin (atrophy), and small clusters of blood vessels just under the skin (telangiectases). These chronic skin problems are collectively known as poikiloderma. The varied signs and symptoms of Baller-Gerold syndrome overlap with features of other disorders, namely Rothmund-Thomson syndrome and RAPADILINO syndrome. These syndromes are also characterized by radial ray defects, skeletal abnormalities, and slow growth. All of these conditions can be caused by mutations in the same gene. Based on these similarities, researchers are investigating whether Baller-Gerold syndrome, Rothmund-Thomson syndrome, and RAPADILINO syndrome are separate disorders or part of a single syndrome with overlapping signs and symptoms. The prevalence of Baller-Gerold syndrome is unknown, but this rare condition probably affects fewer than 1 per million people. Fewer than 40 cases have been reported in the medical literature. Mutations in the RECQL4 gene cause some cases of Baller-Gerold syndrome. This gene provides instructions for making one member of a protein family called RecQ helicases. Helicases are enzymes that bind to DNA and temporarily unwind the two spiral strands (double helix) of the DNA molecule. This unwinding is necessary for copying (replicating) DNA in preparation for cell division, and for repairing damaged DNA. The RECQL4 protein helps stabilize genetic information in the body's cells and plays a role in replicating and repairing DNA. Mutations in the RECQL4 gene prevent cells from producing any RECQL4 protein or change the way the protein is pieced together, which disrupts its usual function. A shortage of this protein may prevent normal DNA replication and repair, causing widespread damage to a person's genetic information over time. It is unclear how a loss of this protein's activity leads to the signs and symptoms of Baller-Gerold syndrome. This condition has been associated with prenatal (before birth) exposure to a drug called sodium valproate. This medication is used to treat epilepsy and certain psychiatric disorders. Some infants whose mothers took sodium valproate during pregnancy were born with the characteristic features of Baller-Gerold syndrome, such as an unusual skull shape, distinctive facial features, and abnormalities of the arms and hands. However, it is unclear if exposure to the medication caused the condition. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by Baller-Gerold syndrome ? | The prevalence of Baller-Gerold syndrome is unknown, but this rare condition probably affects fewer than 1 per million people. Fewer than 40 cases have been reported in the medical literature. |
Baller-Gerold syndrome is a rare condition characterized by the premature fusion of certain skull bones (craniosynostosis) and abnormalities of bones in the arms and hands. People with Baller-Gerold syndrome have prematurely fused skull bones, most often along the coronal suture, the growth line that goes over the head from ear to ear. Other sutures of the skull may be fused as well. These changes result in an abnormally shaped head, a prominent forehead, and bulging eyes with shallow eye sockets (ocular proptosis). Other distinctive facial features can include widely spaced eyes (hypertelorism), a small mouth, and a saddle-shaped or underdeveloped nose. Bone abnormalities in the hands include missing fingers (oligodactyly) and malformed or absent thumbs. Partial or complete absence of bones in the forearm is also common. Together, these hand and arm abnormalities are called radial ray malformations. People with Baller-Gerold syndrome may have a variety of additional signs and symptoms including slow growth beginning in infancy, small stature, and malformed or missing kneecaps (patellae). A skin rash often appears on the arms and legs a few months after birth. This rash spreads over time, causing patchy changes in skin coloring, areas of thinning skin (atrophy), and small clusters of blood vessels just under the skin (telangiectases). These chronic skin problems are collectively known as poikiloderma. The varied signs and symptoms of Baller-Gerold syndrome overlap with features of other disorders, namely Rothmund-Thomson syndrome and RAPADILINO syndrome. These syndromes are also characterized by radial ray defects, skeletal abnormalities, and slow growth. All of these conditions can be caused by mutations in the same gene. Based on these similarities, researchers are investigating whether Baller-Gerold syndrome, Rothmund-Thomson syndrome, and RAPADILINO syndrome are separate disorders or part of a single syndrome with overlapping signs and symptoms. The prevalence of Baller-Gerold syndrome is unknown, but this rare condition probably affects fewer than 1 per million people. Fewer than 40 cases have been reported in the medical literature. Mutations in the RECQL4 gene cause some cases of Baller-Gerold syndrome. This gene provides instructions for making one member of a protein family called RecQ helicases. Helicases are enzymes that bind to DNA and temporarily unwind the two spiral strands (double helix) of the DNA molecule. This unwinding is necessary for copying (replicating) DNA in preparation for cell division, and for repairing damaged DNA. The RECQL4 protein helps stabilize genetic information in the body's cells and plays a role in replicating and repairing DNA. Mutations in the RECQL4 gene prevent cells from producing any RECQL4 protein or change the way the protein is pieced together, which disrupts its usual function. A shortage of this protein may prevent normal DNA replication and repair, causing widespread damage to a person's genetic information over time. It is unclear how a loss of this protein's activity leads to the signs and symptoms of Baller-Gerold syndrome. This condition has been associated with prenatal (before birth) exposure to a drug called sodium valproate. This medication is used to treat epilepsy and certain psychiatric disorders. Some infants whose mothers took sodium valproate during pregnancy were born with the characteristic features of Baller-Gerold syndrome, such as an unusual skull shape, distinctive facial features, and abnormalities of the arms and hands. However, it is unclear if exposure to the medication caused the condition. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to Baller-Gerold syndrome ? | Mutations in the RECQL4 gene cause some cases of Baller-Gerold syndrome. This gene provides instructions for making one member of a protein family called RecQ helicases. Helicases are enzymes that bind to DNA and temporarily unwind the two spiral strands (double helix) of the DNA molecule. This unwinding is necessary for copying (replicating) DNA in preparation for cell division, and for repairing damaged DNA. The RECQL4 protein helps stabilize genetic information in the body's cells and plays a role in replicating and repairing DNA. Mutations in the RECQL4 gene prevent cells from producing any RECQL4 protein or change the way the protein is pieced together, which disrupts its usual function. A shortage of this protein may prevent normal DNA replication and repair, causing widespread damage to a person's genetic information over time. It is unclear how a loss of this protein's activity leads to the signs and symptoms of Baller-Gerold syndrome. This condition has been associated with prenatal (before birth) exposure to a drug called sodium valproate. This medication is used to treat epilepsy and certain psychiatric disorders. Some infants whose mothers took sodium valproate during pregnancy were born with the characteristic features of Baller-Gerold syndrome, such as an unusual skull shape, distinctive facial features, and abnormalities of the arms and hands. However, it is unclear if exposure to the medication caused the condition. |
Baller-Gerold syndrome is a rare condition characterized by the premature fusion of certain skull bones (craniosynostosis) and abnormalities of bones in the arms and hands. People with Baller-Gerold syndrome have prematurely fused skull bones, most often along the coronal suture, the growth line that goes over the head from ear to ear. Other sutures of the skull may be fused as well. These changes result in an abnormally shaped head, a prominent forehead, and bulging eyes with shallow eye sockets (ocular proptosis). Other distinctive facial features can include widely spaced eyes (hypertelorism), a small mouth, and a saddle-shaped or underdeveloped nose. Bone abnormalities in the hands include missing fingers (oligodactyly) and malformed or absent thumbs. Partial or complete absence of bones in the forearm is also common. Together, these hand and arm abnormalities are called radial ray malformations. People with Baller-Gerold syndrome may have a variety of additional signs and symptoms including slow growth beginning in infancy, small stature, and malformed or missing kneecaps (patellae). A skin rash often appears on the arms and legs a few months after birth. This rash spreads over time, causing patchy changes in skin coloring, areas of thinning skin (atrophy), and small clusters of blood vessels just under the skin (telangiectases). These chronic skin problems are collectively known as poikiloderma. The varied signs and symptoms of Baller-Gerold syndrome overlap with features of other disorders, namely Rothmund-Thomson syndrome and RAPADILINO syndrome. These syndromes are also characterized by radial ray defects, skeletal abnormalities, and slow growth. All of these conditions can be caused by mutations in the same gene. Based on these similarities, researchers are investigating whether Baller-Gerold syndrome, Rothmund-Thomson syndrome, and RAPADILINO syndrome are separate disorders or part of a single syndrome with overlapping signs and symptoms. The prevalence of Baller-Gerold syndrome is unknown, but this rare condition probably affects fewer than 1 per million people. Fewer than 40 cases have been reported in the medical literature. Mutations in the RECQL4 gene cause some cases of Baller-Gerold syndrome. This gene provides instructions for making one member of a protein family called RecQ helicases. Helicases are enzymes that bind to DNA and temporarily unwind the two spiral strands (double helix) of the DNA molecule. This unwinding is necessary for copying (replicating) DNA in preparation for cell division, and for repairing damaged DNA. The RECQL4 protein helps stabilize genetic information in the body's cells and plays a role in replicating and repairing DNA. Mutations in the RECQL4 gene prevent cells from producing any RECQL4 protein or change the way the protein is pieced together, which disrupts its usual function. A shortage of this protein may prevent normal DNA replication and repair, causing widespread damage to a person's genetic information over time. It is unclear how a loss of this protein's activity leads to the signs and symptoms of Baller-Gerold syndrome. This condition has been associated with prenatal (before birth) exposure to a drug called sodium valproate. This medication is used to treat epilepsy and certain psychiatric disorders. Some infants whose mothers took sodium valproate during pregnancy were born with the characteristic features of Baller-Gerold syndrome, such as an unusual skull shape, distinctive facial features, and abnormalities of the arms and hands. However, it is unclear if exposure to the medication caused the condition. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is Baller-Gerold syndrome inherited ? | This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. |
Baller-Gerold syndrome is a rare condition characterized by the premature fusion of certain skull bones (craniosynostosis) and abnormalities of bones in the arms and hands. People with Baller-Gerold syndrome have prematurely fused skull bones, most often along the coronal suture, the growth line that goes over the head from ear to ear. Other sutures of the skull may be fused as well. These changes result in an abnormally shaped head, a prominent forehead, and bulging eyes with shallow eye sockets (ocular proptosis). Other distinctive facial features can include widely spaced eyes (hypertelorism), a small mouth, and a saddle-shaped or underdeveloped nose. Bone abnormalities in the hands include missing fingers (oligodactyly) and malformed or absent thumbs. Partial or complete absence of bones in the forearm is also common. Together, these hand and arm abnormalities are called radial ray malformations. People with Baller-Gerold syndrome may have a variety of additional signs and symptoms including slow growth beginning in infancy, small stature, and malformed or missing kneecaps (patellae). A skin rash often appears on the arms and legs a few months after birth. This rash spreads over time, causing patchy changes in skin coloring, areas of thinning skin (atrophy), and small clusters of blood vessels just under the skin (telangiectases). These chronic skin problems are collectively known as poikiloderma. The varied signs and symptoms of Baller-Gerold syndrome overlap with features of other disorders, namely Rothmund-Thomson syndrome and RAPADILINO syndrome. These syndromes are also characterized by radial ray defects, skeletal abnormalities, and slow growth. All of these conditions can be caused by mutations in the same gene. Based on these similarities, researchers are investigating whether Baller-Gerold syndrome, Rothmund-Thomson syndrome, and RAPADILINO syndrome are separate disorders or part of a single syndrome with overlapping signs and symptoms. The prevalence of Baller-Gerold syndrome is unknown, but this rare condition probably affects fewer than 1 per million people. Fewer than 40 cases have been reported in the medical literature. Mutations in the RECQL4 gene cause some cases of Baller-Gerold syndrome. This gene provides instructions for making one member of a protein family called RecQ helicases. Helicases are enzymes that bind to DNA and temporarily unwind the two spiral strands (double helix) of the DNA molecule. This unwinding is necessary for copying (replicating) DNA in preparation for cell division, and for repairing damaged DNA. The RECQL4 protein helps stabilize genetic information in the body's cells and plays a role in replicating and repairing DNA. Mutations in the RECQL4 gene prevent cells from producing any RECQL4 protein or change the way the protein is pieced together, which disrupts its usual function. A shortage of this protein may prevent normal DNA replication and repair, causing widespread damage to a person's genetic information over time. It is unclear how a loss of this protein's activity leads to the signs and symptoms of Baller-Gerold syndrome. This condition has been associated with prenatal (before birth) exposure to a drug called sodium valproate. This medication is used to treat epilepsy and certain psychiatric disorders. Some infants whose mothers took sodium valproate during pregnancy were born with the characteristic features of Baller-Gerold syndrome, such as an unusual skull shape, distinctive facial features, and abnormalities of the arms and hands. However, it is unclear if exposure to the medication caused the condition. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for Baller-Gerold syndrome ? | These resources address the diagnosis or management of Baller-Gerold syndrome: - Gene Review: Gene Review: Baller-Gerold Syndrome - Genetic Testing Registry: Baller-Gerold syndrome - MedlinePlus Encyclopedia: Craniosynostosis - MedlinePlus Encyclopedia: Skull of a Newborn (image) These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Kleefstra syndrome is a disorder that involves many parts of the body. Characteristic features of Kleefstra syndrome include developmental delay and intellectual disability, severely limited or absent speech, and weak muscle tone (hypotonia). Affected individuals also have an unusually small head size (microcephaly) and a wide, short skull (brachycephaly). Distinctive facial features include eyebrows that grow together in the middle (synophrys), widely spaced eyes (hypertelorism), a sunken appearance of the middle of the face (midface hypoplasia), nostrils that open to the front rather than downward (anteverted nares), a protruding jaw (prognathism), rolled out (everted) lips, and a large tongue (macroglossia). Affected individuals may have a high birth weight and childhood obesity. People with Kleefstra syndrome may also have structural brain abnormalities, congenital heart defects, genitourinary abnormalities, seizures, and a tendency to develop severe respiratory infections. During childhood they may exhibit features of autism or related developmental disorders affecting communication and social interaction. In adolescence, they may develop a general loss of interest and enthusiasm (apathy) or unresponsiveness (catatonia). The prevalence of Kleefstra syndrome is unknown. Only recently has testing become available to distinguish it from other disorders with similar features. Kleefstra syndrome is caused by the loss of the EHMT1 gene or by mutations that disable its function. The EHMT1 gene provides instructions for making an enzyme called euchromatic histone methyltransferase 1. Histone methyltransferases are enzymes that modify proteins called histones. Histones are structural proteins that attach (bind) to DNA and give chromosomes their shape. By adding a molecule called a methyl group to histones, histone methyltransferases can turn off (suppress) the activity of certain genes, which is essential for normal development and function. Most people with Kleefstra syndrome are missing a sequence of about 1 million DNA building blocks (base pairs) on one copy of chromosome 9 in each cell. The deletion occurs near the end of the long (q) arm of the chromosome at a location designated q34.3, a region containing the EHMT1 gene. Some affected individuals have shorter or longer deletions in the same region. The loss of the EHMT1 gene from one copy of chromosome 9 in each cell is believed to be responsible for the characteristic features of Kleefstra syndrome in people with the 9q34.3 deletion. However, the loss of other genes in the same region may lead to additional health problems in some affected individuals. About 25 percent of individuals with Kleefstra syndrome do not have a deletion of genetic material from chromosome 9; instead, these individuals have mutations in the EHMT1 gene. Some of these mutations change single protein building blocks (amino acids) in euchromatic histone methyltransferase 1. Others create a premature stop signal in the instructions for making the enzyme or alter the way the gene's instructions are pieced together to produce the enzyme. These changes generally result in an enzyme that is unstable and decays rapidly, or that is disabled and cannot function properly. Either a deletion or a mutation affecting the EHMT1 gene results in a lack of functional euchromatic histone methyltransferase 1 enzyme. A lack of this enzyme impairs proper control of the activity of certain genes in many of the body's organs and tissues, resulting in the abnormalities of development and function characteristic of Kleefstra syndrome. The inheritance of Kleefstra syndrome is considered to be autosomal dominant because a deletion in one copy of chromosome 9 in each cell or a mutation in one copy of the EHMT1 gene is sufficient to cause the condition. Most cases of Kleefstra syndrome are not inherited, however. The genetic change occurs most often as a random event during the formation of reproductive cells (eggs or sperm) or in early fetal development. Affected people typically have no history of the disorder in their family, though they can pass the disorder on to their children. Only a few people with Kleefstra syndrome have been known to reproduce. Rarely, affected individuals inherit a chromosome 9 with a deleted segment from an unaffected parent. In these cases, the parent carries a chromosomal rearrangement called a balanced translocation, in which no genetic material is gained or lost. Balanced translocations usually do not cause any health problems; however, they can become unbalanced as they are passed to the next generation. Children who inherit an unbalanced translocation can have a chromosomal rearrangement with extra or missing genetic material. Individuals with Kleefstra syndrome who inherit an unbalanced translocation are missing genetic material from the long arm of chromosome 9. A few individuals with Kleefstra syndrome have inherited the chromosome 9q34.3 deletion from an unaffected parent who is mosaic for the deletion. Mosaic means that an individual has the deletion in some cells (including some sperm or egg cells), but not in others. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) Kleefstra syndrome ? | Kleefstra syndrome is a disorder that involves many parts of the body. Characteristic features of Kleefstra syndrome include developmental delay and intellectual disability, severely limited or absent speech, and weak muscle tone (hypotonia). Affected individuals also have an unusually small head size (microcephaly) and a wide, short skull (brachycephaly). Distinctive facial features include eyebrows that grow together in the middle (synophrys), widely spaced eyes (hypertelorism), a sunken appearance of the middle of the face (midface hypoplasia), nostrils that open to the front rather than downward (anteverted nares), a protruding jaw (prognathism), rolled out (everted) lips, and a large tongue (macroglossia). Affected individuals may have a high birth weight and childhood obesity. People with Kleefstra syndrome may also have structural brain abnormalities, congenital heart defects, genitourinary abnormalities, seizures, and a tendency to develop severe respiratory infections. During childhood they may exhibit features of autism or related developmental disorders affecting communication and social interaction. In adolescence, they may develop a general loss of interest and enthusiasm (apathy) or unresponsiveness (catatonia). |
Kleefstra syndrome is a disorder that involves many parts of the body. Characteristic features of Kleefstra syndrome include developmental delay and intellectual disability, severely limited or absent speech, and weak muscle tone (hypotonia). Affected individuals also have an unusually small head size (microcephaly) and a wide, short skull (brachycephaly). Distinctive facial features include eyebrows that grow together in the middle (synophrys), widely spaced eyes (hypertelorism), a sunken appearance of the middle of the face (midface hypoplasia), nostrils that open to the front rather than downward (anteverted nares), a protruding jaw (prognathism), rolled out (everted) lips, and a large tongue (macroglossia). Affected individuals may have a high birth weight and childhood obesity. People with Kleefstra syndrome may also have structural brain abnormalities, congenital heart defects, genitourinary abnormalities, seizures, and a tendency to develop severe respiratory infections. During childhood they may exhibit features of autism or related developmental disorders affecting communication and social interaction. In adolescence, they may develop a general loss of interest and enthusiasm (apathy) or unresponsiveness (catatonia). The prevalence of Kleefstra syndrome is unknown. Only recently has testing become available to distinguish it from other disorders with similar features. Kleefstra syndrome is caused by the loss of the EHMT1 gene or by mutations that disable its function. The EHMT1 gene provides instructions for making an enzyme called euchromatic histone methyltransferase 1. Histone methyltransferases are enzymes that modify proteins called histones. Histones are structural proteins that attach (bind) to DNA and give chromosomes their shape. By adding a molecule called a methyl group to histones, histone methyltransferases can turn off (suppress) the activity of certain genes, which is essential for normal development and function. Most people with Kleefstra syndrome are missing a sequence of about 1 million DNA building blocks (base pairs) on one copy of chromosome 9 in each cell. The deletion occurs near the end of the long (q) arm of the chromosome at a location designated q34.3, a region containing the EHMT1 gene. Some affected individuals have shorter or longer deletions in the same region. The loss of the EHMT1 gene from one copy of chromosome 9 in each cell is believed to be responsible for the characteristic features of Kleefstra syndrome in people with the 9q34.3 deletion. However, the loss of other genes in the same region may lead to additional health problems in some affected individuals. About 25 percent of individuals with Kleefstra syndrome do not have a deletion of genetic material from chromosome 9; instead, these individuals have mutations in the EHMT1 gene. Some of these mutations change single protein building blocks (amino acids) in euchromatic histone methyltransferase 1. Others create a premature stop signal in the instructions for making the enzyme or alter the way the gene's instructions are pieced together to produce the enzyme. These changes generally result in an enzyme that is unstable and decays rapidly, or that is disabled and cannot function properly. Either a deletion or a mutation affecting the EHMT1 gene results in a lack of functional euchromatic histone methyltransferase 1 enzyme. A lack of this enzyme impairs proper control of the activity of certain genes in many of the body's organs and tissues, resulting in the abnormalities of development and function characteristic of Kleefstra syndrome. The inheritance of Kleefstra syndrome is considered to be autosomal dominant because a deletion in one copy of chromosome 9 in each cell or a mutation in one copy of the EHMT1 gene is sufficient to cause the condition. Most cases of Kleefstra syndrome are not inherited, however. The genetic change occurs most often as a random event during the formation of reproductive cells (eggs or sperm) or in early fetal development. Affected people typically have no history of the disorder in their family, though they can pass the disorder on to their children. Only a few people with Kleefstra syndrome have been known to reproduce. Rarely, affected individuals inherit a chromosome 9 with a deleted segment from an unaffected parent. In these cases, the parent carries a chromosomal rearrangement called a balanced translocation, in which no genetic material is gained or lost. Balanced translocations usually do not cause any health problems; however, they can become unbalanced as they are passed to the next generation. Children who inherit an unbalanced translocation can have a chromosomal rearrangement with extra or missing genetic material. Individuals with Kleefstra syndrome who inherit an unbalanced translocation are missing genetic material from the long arm of chromosome 9. A few individuals with Kleefstra syndrome have inherited the chromosome 9q34.3 deletion from an unaffected parent who is mosaic for the deletion. Mosaic means that an individual has the deletion in some cells (including some sperm or egg cells), but not in others. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by Kleefstra syndrome ? | The prevalence of Kleefstra syndrome is unknown. Only recently has testing become available to distinguish it from other disorders with similar features. |
Kleefstra syndrome is a disorder that involves many parts of the body. Characteristic features of Kleefstra syndrome include developmental delay and intellectual disability, severely limited or absent speech, and weak muscle tone (hypotonia). Affected individuals also have an unusually small head size (microcephaly) and a wide, short skull (brachycephaly). Distinctive facial features include eyebrows that grow together in the middle (synophrys), widely spaced eyes (hypertelorism), a sunken appearance of the middle of the face (midface hypoplasia), nostrils that open to the front rather than downward (anteverted nares), a protruding jaw (prognathism), rolled out (everted) lips, and a large tongue (macroglossia). Affected individuals may have a high birth weight and childhood obesity. People with Kleefstra syndrome may also have structural brain abnormalities, congenital heart defects, genitourinary abnormalities, seizures, and a tendency to develop severe respiratory infections. During childhood they may exhibit features of autism or related developmental disorders affecting communication and social interaction. In adolescence, they may develop a general loss of interest and enthusiasm (apathy) or unresponsiveness (catatonia). The prevalence of Kleefstra syndrome is unknown. Only recently has testing become available to distinguish it from other disorders with similar features. Kleefstra syndrome is caused by the loss of the EHMT1 gene or by mutations that disable its function. The EHMT1 gene provides instructions for making an enzyme called euchromatic histone methyltransferase 1. Histone methyltransferases are enzymes that modify proteins called histones. Histones are structural proteins that attach (bind) to DNA and give chromosomes their shape. By adding a molecule called a methyl group to histones, histone methyltransferases can turn off (suppress) the activity of certain genes, which is essential for normal development and function. Most people with Kleefstra syndrome are missing a sequence of about 1 million DNA building blocks (base pairs) on one copy of chromosome 9 in each cell. The deletion occurs near the end of the long (q) arm of the chromosome at a location designated q34.3, a region containing the EHMT1 gene. Some affected individuals have shorter or longer deletions in the same region. The loss of the EHMT1 gene from one copy of chromosome 9 in each cell is believed to be responsible for the characteristic features of Kleefstra syndrome in people with the 9q34.3 deletion. However, the loss of other genes in the same region may lead to additional health problems in some affected individuals. About 25 percent of individuals with Kleefstra syndrome do not have a deletion of genetic material from chromosome 9; instead, these individuals have mutations in the EHMT1 gene. Some of these mutations change single protein building blocks (amino acids) in euchromatic histone methyltransferase 1. Others create a premature stop signal in the instructions for making the enzyme or alter the way the gene's instructions are pieced together to produce the enzyme. These changes generally result in an enzyme that is unstable and decays rapidly, or that is disabled and cannot function properly. Either a deletion or a mutation affecting the EHMT1 gene results in a lack of functional euchromatic histone methyltransferase 1 enzyme. A lack of this enzyme impairs proper control of the activity of certain genes in many of the body's organs and tissues, resulting in the abnormalities of development and function characteristic of Kleefstra syndrome. The inheritance of Kleefstra syndrome is considered to be autosomal dominant because a deletion in one copy of chromosome 9 in each cell or a mutation in one copy of the EHMT1 gene is sufficient to cause the condition. Most cases of Kleefstra syndrome are not inherited, however. The genetic change occurs most often as a random event during the formation of reproductive cells (eggs or sperm) or in early fetal development. Affected people typically have no history of the disorder in their family, though they can pass the disorder on to their children. Only a few people with Kleefstra syndrome have been known to reproduce. Rarely, affected individuals inherit a chromosome 9 with a deleted segment from an unaffected parent. In these cases, the parent carries a chromosomal rearrangement called a balanced translocation, in which no genetic material is gained or lost. Balanced translocations usually do not cause any health problems; however, they can become unbalanced as they are passed to the next generation. Children who inherit an unbalanced translocation can have a chromosomal rearrangement with extra or missing genetic material. Individuals with Kleefstra syndrome who inherit an unbalanced translocation are missing genetic material from the long arm of chromosome 9. A few individuals with Kleefstra syndrome have inherited the chromosome 9q34.3 deletion from an unaffected parent who is mosaic for the deletion. Mosaic means that an individual has the deletion in some cells (including some sperm or egg cells), but not in others. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to Kleefstra syndrome ? | Kleefstra syndrome is caused by the loss of the EHMT1 gene or by mutations that disable its function. The EHMT1 gene provides instructions for making an enzyme called euchromatic histone methyltransferase 1. Histone methyltransferases are enzymes that modify proteins called histones. Histones are structural proteins that attach (bind) to DNA and give chromosomes their shape. By adding a molecule called a methyl group to histones, histone methyltransferases can turn off (suppress) the activity of certain genes, which is essential for normal development and function. Most people with Kleefstra syndrome are missing a sequence of about 1 million DNA building blocks (base pairs) on one copy of chromosome 9 in each cell. The deletion occurs near the end of the long (q) arm of the chromosome at a location designated q34.3, a region containing the EHMT1 gene. Some affected individuals have shorter or longer deletions in the same region. The loss of the EHMT1 gene from one copy of chromosome 9 in each cell is believed to be responsible for the characteristic features of Kleefstra syndrome in people with the 9q34.3 deletion. However, the loss of other genes in the same region may lead to additional health problems in some affected individuals. About 25 percent of individuals with Kleefstra syndrome do not have a deletion of genetic material from chromosome 9; instead, these individuals have mutations in the EHMT1 gene. Some of these mutations change single protein building blocks (amino acids) in euchromatic histone methyltransferase 1. Others create a premature stop signal in the instructions for making the enzyme or alter the way the gene's instructions are pieced together to produce the enzyme. These changes generally result in an enzyme that is unstable and decays rapidly, or that is disabled and cannot function properly. Either a deletion or a mutation affecting the EHMT1 gene results in a lack of functional euchromatic histone methyltransferase 1 enzyme. A lack of this enzyme impairs proper control of the activity of certain genes in many of the body's organs and tissues, resulting in the abnormalities of development and function characteristic of Kleefstra syndrome. |
Kleefstra syndrome is a disorder that involves many parts of the body. Characteristic features of Kleefstra syndrome include developmental delay and intellectual disability, severely limited or absent speech, and weak muscle tone (hypotonia). Affected individuals also have an unusually small head size (microcephaly) and a wide, short skull (brachycephaly). Distinctive facial features include eyebrows that grow together in the middle (synophrys), widely spaced eyes (hypertelorism), a sunken appearance of the middle of the face (midface hypoplasia), nostrils that open to the front rather than downward (anteverted nares), a protruding jaw (prognathism), rolled out (everted) lips, and a large tongue (macroglossia). Affected individuals may have a high birth weight and childhood obesity. People with Kleefstra syndrome may also have structural brain abnormalities, congenital heart defects, genitourinary abnormalities, seizures, and a tendency to develop severe respiratory infections. During childhood they may exhibit features of autism or related developmental disorders affecting communication and social interaction. In adolescence, they may develop a general loss of interest and enthusiasm (apathy) or unresponsiveness (catatonia). The prevalence of Kleefstra syndrome is unknown. Only recently has testing become available to distinguish it from other disorders with similar features. Kleefstra syndrome is caused by the loss of the EHMT1 gene or by mutations that disable its function. The EHMT1 gene provides instructions for making an enzyme called euchromatic histone methyltransferase 1. Histone methyltransferases are enzymes that modify proteins called histones. Histones are structural proteins that attach (bind) to DNA and give chromosomes their shape. By adding a molecule called a methyl group to histones, histone methyltransferases can turn off (suppress) the activity of certain genes, which is essential for normal development and function. Most people with Kleefstra syndrome are missing a sequence of about 1 million DNA building blocks (base pairs) on one copy of chromosome 9 in each cell. The deletion occurs near the end of the long (q) arm of the chromosome at a location designated q34.3, a region containing the EHMT1 gene. Some affected individuals have shorter or longer deletions in the same region. The loss of the EHMT1 gene from one copy of chromosome 9 in each cell is believed to be responsible for the characteristic features of Kleefstra syndrome in people with the 9q34.3 deletion. However, the loss of other genes in the same region may lead to additional health problems in some affected individuals. About 25 percent of individuals with Kleefstra syndrome do not have a deletion of genetic material from chromosome 9; instead, these individuals have mutations in the EHMT1 gene. Some of these mutations change single protein building blocks (amino acids) in euchromatic histone methyltransferase 1. Others create a premature stop signal in the instructions for making the enzyme or alter the way the gene's instructions are pieced together to produce the enzyme. These changes generally result in an enzyme that is unstable and decays rapidly, or that is disabled and cannot function properly. Either a deletion or a mutation affecting the EHMT1 gene results in a lack of functional euchromatic histone methyltransferase 1 enzyme. A lack of this enzyme impairs proper control of the activity of certain genes in many of the body's organs and tissues, resulting in the abnormalities of development and function characteristic of Kleefstra syndrome. The inheritance of Kleefstra syndrome is considered to be autosomal dominant because a deletion in one copy of chromosome 9 in each cell or a mutation in one copy of the EHMT1 gene is sufficient to cause the condition. Most cases of Kleefstra syndrome are not inherited, however. The genetic change occurs most often as a random event during the formation of reproductive cells (eggs or sperm) or in early fetal development. Affected people typically have no history of the disorder in their family, though they can pass the disorder on to their children. Only a few people with Kleefstra syndrome have been known to reproduce. Rarely, affected individuals inherit a chromosome 9 with a deleted segment from an unaffected parent. In these cases, the parent carries a chromosomal rearrangement called a balanced translocation, in which no genetic material is gained or lost. Balanced translocations usually do not cause any health problems; however, they can become unbalanced as they are passed to the next generation. Children who inherit an unbalanced translocation can have a chromosomal rearrangement with extra or missing genetic material. Individuals with Kleefstra syndrome who inherit an unbalanced translocation are missing genetic material from the long arm of chromosome 9. A few individuals with Kleefstra syndrome have inherited the chromosome 9q34.3 deletion from an unaffected parent who is mosaic for the deletion. Mosaic means that an individual has the deletion in some cells (including some sperm or egg cells), but not in others. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is Kleefstra syndrome inherited ? | The inheritance of Kleefstra syndrome is considered to be autosomal dominant because a deletion in one copy of chromosome 9 in each cell or a mutation in one copy of the EHMT1 gene is sufficient to cause the condition. Most cases of Kleefstra syndrome are not inherited, however. The genetic change occurs most often as a random event during the formation of reproductive cells (eggs or sperm) or in early fetal development. Affected people typically have no history of the disorder in their family, though they can pass the disorder on to their children. Only a few people with Kleefstra syndrome have been known to reproduce. Rarely, affected individuals inherit a chromosome 9 with a deleted segment from an unaffected parent. In these cases, the parent carries a chromosomal rearrangement called a balanced translocation, in which no genetic material is gained or lost. Balanced translocations usually do not cause any health problems; however, they can become unbalanced as they are passed to the next generation. Children who inherit an unbalanced translocation can have a chromosomal rearrangement with extra or missing genetic material. Individuals with Kleefstra syndrome who inherit an unbalanced translocation are missing genetic material from the long arm of chromosome 9. A few individuals with Kleefstra syndrome have inherited the chromosome 9q34.3 deletion from an unaffected parent who is mosaic for the deletion. Mosaic means that an individual has the deletion in some cells (including some sperm or egg cells), but not in others. |
Kleefstra syndrome is a disorder that involves many parts of the body. Characteristic features of Kleefstra syndrome include developmental delay and intellectual disability, severely limited or absent speech, and weak muscle tone (hypotonia). Affected individuals also have an unusually small head size (microcephaly) and a wide, short skull (brachycephaly). Distinctive facial features include eyebrows that grow together in the middle (synophrys), widely spaced eyes (hypertelorism), a sunken appearance of the middle of the face (midface hypoplasia), nostrils that open to the front rather than downward (anteverted nares), a protruding jaw (prognathism), rolled out (everted) lips, and a large tongue (macroglossia). Affected individuals may have a high birth weight and childhood obesity. People with Kleefstra syndrome may also have structural brain abnormalities, congenital heart defects, genitourinary abnormalities, seizures, and a tendency to develop severe respiratory infections. During childhood they may exhibit features of autism or related developmental disorders affecting communication and social interaction. In adolescence, they may develop a general loss of interest and enthusiasm (apathy) or unresponsiveness (catatonia). The prevalence of Kleefstra syndrome is unknown. Only recently has testing become available to distinguish it from other disorders with similar features. Kleefstra syndrome is caused by the loss of the EHMT1 gene or by mutations that disable its function. The EHMT1 gene provides instructions for making an enzyme called euchromatic histone methyltransferase 1. Histone methyltransferases are enzymes that modify proteins called histones. Histones are structural proteins that attach (bind) to DNA and give chromosomes their shape. By adding a molecule called a methyl group to histones, histone methyltransferases can turn off (suppress) the activity of certain genes, which is essential for normal development and function. Most people with Kleefstra syndrome are missing a sequence of about 1 million DNA building blocks (base pairs) on one copy of chromosome 9 in each cell. The deletion occurs near the end of the long (q) arm of the chromosome at a location designated q34.3, a region containing the EHMT1 gene. Some affected individuals have shorter or longer deletions in the same region. The loss of the EHMT1 gene from one copy of chromosome 9 in each cell is believed to be responsible for the characteristic features of Kleefstra syndrome in people with the 9q34.3 deletion. However, the loss of other genes in the same region may lead to additional health problems in some affected individuals. About 25 percent of individuals with Kleefstra syndrome do not have a deletion of genetic material from chromosome 9; instead, these individuals have mutations in the EHMT1 gene. Some of these mutations change single protein building blocks (amino acids) in euchromatic histone methyltransferase 1. Others create a premature stop signal in the instructions for making the enzyme or alter the way the gene's instructions are pieced together to produce the enzyme. These changes generally result in an enzyme that is unstable and decays rapidly, or that is disabled and cannot function properly. Either a deletion or a mutation affecting the EHMT1 gene results in a lack of functional euchromatic histone methyltransferase 1 enzyme. A lack of this enzyme impairs proper control of the activity of certain genes in many of the body's organs and tissues, resulting in the abnormalities of development and function characteristic of Kleefstra syndrome. The inheritance of Kleefstra syndrome is considered to be autosomal dominant because a deletion in one copy of chromosome 9 in each cell or a mutation in one copy of the EHMT1 gene is sufficient to cause the condition. Most cases of Kleefstra syndrome are not inherited, however. The genetic change occurs most often as a random event during the formation of reproductive cells (eggs or sperm) or in early fetal development. Affected people typically have no history of the disorder in their family, though they can pass the disorder on to their children. Only a few people with Kleefstra syndrome have been known to reproduce. Rarely, affected individuals inherit a chromosome 9 with a deleted segment from an unaffected parent. In these cases, the parent carries a chromosomal rearrangement called a balanced translocation, in which no genetic material is gained or lost. Balanced translocations usually do not cause any health problems; however, they can become unbalanced as they are passed to the next generation. Children who inherit an unbalanced translocation can have a chromosomal rearrangement with extra or missing genetic material. Individuals with Kleefstra syndrome who inherit an unbalanced translocation are missing genetic material from the long arm of chromosome 9. A few individuals with Kleefstra syndrome have inherited the chromosome 9q34.3 deletion from an unaffected parent who is mosaic for the deletion. Mosaic means that an individual has the deletion in some cells (including some sperm or egg cells), but not in others. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for Kleefstra syndrome ? | These resources address the diagnosis or management of Kleefstra syndrome: - Gene Review: Gene Review: Kleefstra Syndrome - Genetic Testing Registry: Chromosome 9q deletion syndrome These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Myotonia congenita is a disorder that affects muscles used for movement (skeletal muscles). Beginning in childhood, people with this condition experience bouts of sustained muscle tensing (myotonia) that prevent muscles from relaxing normally. Although myotonia can affect any skeletal muscles, including muscles of the face and tongue, it occurs most often in the legs. Myotonia causes muscle stiffness that can interfere with movement. In some people the stiffness is very mild, while in other cases it may be severe enough to interfere with walking, running, and other activities of daily life. These muscle problems are particularly noticeable during movement following a period of rest. Many affected individuals find that repeated movements can temporarily alleviate their muscle stiffness, a phenomenon known as the warm-up effect. The two major types of myotonia congenita are known as Thomsen disease and Becker disease. These conditions are distinguished by the severity of their symptoms and their patterns of inheritance. Becker disease usually appears later in childhood than Thomsen disease and causes more severe muscle stiffness, particularly in males. People with Becker disease often experience temporary attacks of muscle weakness, particularly in the arms and hands, brought on by movement after periods of rest. They may also develop mild, permanent muscle weakness over time. This muscle weakness is not seen in people with Thomsen disease. Myotonia congenita is estimated to affect 1 in 100,000 people worldwide. This condition is more common in northern Scandinavia, where it occurs in approximately 1 in 10,000 people. Mutations in the CLCN1 gene cause myotonia congenita. The CLCN1 gene provides instructions for making a protein that is critical for the normal function of skeletal muscle cells. For the body to move normally, skeletal muscles must tense (contract) and relax in a coordinated way. Muscle contraction and relaxation are controlled by the flow of charged atoms (ions) into and out of muscle cells. Specifically, the protein produced from the CLCN1 gene forms a channel that controls the flow of negatively charged chlorine atoms (chloride ions) into these cells. The main function of this channel is to stabilize the cells' electrical charge, which prevents muscles from contracting abnormally. Mutations in the CLCN1 gene alter the usual structure or function of chloride channels. The altered channels cannot properly regulate ion flow, reducing the movement of chloride ions into skeletal muscle cells. This disruption in chloride ion flow triggers prolonged muscle contractions, which are the hallmark of myotonia. The two forms of myotonia congenita have different patterns of inheritance. Thomsen disease is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. Becker disease is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition. Because several CLCN1 mutations can cause either Becker disease or Thomsen disease, doctors usually rely on characteristic signs and symptoms to distinguish the two forms of myotonia congenita. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) myotonia congenita ? | Myotonia congenita is a disorder that affects muscles used for movement (skeletal muscles). Beginning in childhood, people with this condition experience bouts of sustained muscle tensing (myotonia) that prevent muscles from relaxing normally. Although myotonia can affect any skeletal muscles, including muscles of the face and tongue, it occurs most often in the legs. Myotonia causes muscle stiffness that can interfere with movement. In some people the stiffness is very mild, while in other cases it may be severe enough to interfere with walking, running, and other activities of daily life. These muscle problems are particularly noticeable during movement following a period of rest. Many affected individuals find that repeated movements can temporarily alleviate their muscle stiffness, a phenomenon known as the warm-up effect. The two major types of myotonia congenita are known as Thomsen disease and Becker disease. These conditions are distinguished by the severity of their symptoms and their patterns of inheritance. Becker disease usually appears later in childhood than Thomsen disease and causes more severe muscle stiffness, particularly in males. People with Becker disease often experience temporary attacks of muscle weakness, particularly in the arms and hands, brought on by movement after periods of rest. They may also develop mild, permanent muscle weakness over time. This muscle weakness is not seen in people with Thomsen disease. |
Myotonia congenita is a disorder that affects muscles used for movement (skeletal muscles). Beginning in childhood, people with this condition experience bouts of sustained muscle tensing (myotonia) that prevent muscles from relaxing normally. Although myotonia can affect any skeletal muscles, including muscles of the face and tongue, it occurs most often in the legs. Myotonia causes muscle stiffness that can interfere with movement. In some people the stiffness is very mild, while in other cases it may be severe enough to interfere with walking, running, and other activities of daily life. These muscle problems are particularly noticeable during movement following a period of rest. Many affected individuals find that repeated movements can temporarily alleviate their muscle stiffness, a phenomenon known as the warm-up effect. The two major types of myotonia congenita are known as Thomsen disease and Becker disease. These conditions are distinguished by the severity of their symptoms and their patterns of inheritance. Becker disease usually appears later in childhood than Thomsen disease and causes more severe muscle stiffness, particularly in males. People with Becker disease often experience temporary attacks of muscle weakness, particularly in the arms and hands, brought on by movement after periods of rest. They may also develop mild, permanent muscle weakness over time. This muscle weakness is not seen in people with Thomsen disease. Myotonia congenita is estimated to affect 1 in 100,000 people worldwide. This condition is more common in northern Scandinavia, where it occurs in approximately 1 in 10,000 people. Mutations in the CLCN1 gene cause myotonia congenita. The CLCN1 gene provides instructions for making a protein that is critical for the normal function of skeletal muscle cells. For the body to move normally, skeletal muscles must tense (contract) and relax in a coordinated way. Muscle contraction and relaxation are controlled by the flow of charged atoms (ions) into and out of muscle cells. Specifically, the protein produced from the CLCN1 gene forms a channel that controls the flow of negatively charged chlorine atoms (chloride ions) into these cells. The main function of this channel is to stabilize the cells' electrical charge, which prevents muscles from contracting abnormally. Mutations in the CLCN1 gene alter the usual structure or function of chloride channels. The altered channels cannot properly regulate ion flow, reducing the movement of chloride ions into skeletal muscle cells. This disruption in chloride ion flow triggers prolonged muscle contractions, which are the hallmark of myotonia. The two forms of myotonia congenita have different patterns of inheritance. Thomsen disease is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. Becker disease is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition. Because several CLCN1 mutations can cause either Becker disease or Thomsen disease, doctors usually rely on characteristic signs and symptoms to distinguish the two forms of myotonia congenita. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by myotonia congenita ? | Myotonia congenita is estimated to affect 1 in 100,000 people worldwide. This condition is more common in northern Scandinavia, where it occurs in approximately 1 in 10,000 people. |
Myotonia congenita is a disorder that affects muscles used for movement (skeletal muscles). Beginning in childhood, people with this condition experience bouts of sustained muscle tensing (myotonia) that prevent muscles from relaxing normally. Although myotonia can affect any skeletal muscles, including muscles of the face and tongue, it occurs most often in the legs. Myotonia causes muscle stiffness that can interfere with movement. In some people the stiffness is very mild, while in other cases it may be severe enough to interfere with walking, running, and other activities of daily life. These muscle problems are particularly noticeable during movement following a period of rest. Many affected individuals find that repeated movements can temporarily alleviate their muscle stiffness, a phenomenon known as the warm-up effect. The two major types of myotonia congenita are known as Thomsen disease and Becker disease. These conditions are distinguished by the severity of their symptoms and their patterns of inheritance. Becker disease usually appears later in childhood than Thomsen disease and causes more severe muscle stiffness, particularly in males. People with Becker disease often experience temporary attacks of muscle weakness, particularly in the arms and hands, brought on by movement after periods of rest. They may also develop mild, permanent muscle weakness over time. This muscle weakness is not seen in people with Thomsen disease. Myotonia congenita is estimated to affect 1 in 100,000 people worldwide. This condition is more common in northern Scandinavia, where it occurs in approximately 1 in 10,000 people. Mutations in the CLCN1 gene cause myotonia congenita. The CLCN1 gene provides instructions for making a protein that is critical for the normal function of skeletal muscle cells. For the body to move normally, skeletal muscles must tense (contract) and relax in a coordinated way. Muscle contraction and relaxation are controlled by the flow of charged atoms (ions) into and out of muscle cells. Specifically, the protein produced from the CLCN1 gene forms a channel that controls the flow of negatively charged chlorine atoms (chloride ions) into these cells. The main function of this channel is to stabilize the cells' electrical charge, which prevents muscles from contracting abnormally. Mutations in the CLCN1 gene alter the usual structure or function of chloride channels. The altered channels cannot properly regulate ion flow, reducing the movement of chloride ions into skeletal muscle cells. This disruption in chloride ion flow triggers prolonged muscle contractions, which are the hallmark of myotonia. The two forms of myotonia congenita have different patterns of inheritance. Thomsen disease is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. Becker disease is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition. Because several CLCN1 mutations can cause either Becker disease or Thomsen disease, doctors usually rely on characteristic signs and symptoms to distinguish the two forms of myotonia congenita. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to myotonia congenita ? | Mutations in the CLCN1 gene cause myotonia congenita. The CLCN1 gene provides instructions for making a protein that is critical for the normal function of skeletal muscle cells. For the body to move normally, skeletal muscles must tense (contract) and relax in a coordinated way. Muscle contraction and relaxation are controlled by the flow of charged atoms (ions) into and out of muscle cells. Specifically, the protein produced from the CLCN1 gene forms a channel that controls the flow of negatively charged chlorine atoms (chloride ions) into these cells. The main function of this channel is to stabilize the cells' electrical charge, which prevents muscles from contracting abnormally. Mutations in the CLCN1 gene alter the usual structure or function of chloride channels. The altered channels cannot properly regulate ion flow, reducing the movement of chloride ions into skeletal muscle cells. This disruption in chloride ion flow triggers prolonged muscle contractions, which are the hallmark of myotonia. |
Myotonia congenita is a disorder that affects muscles used for movement (skeletal muscles). Beginning in childhood, people with this condition experience bouts of sustained muscle tensing (myotonia) that prevent muscles from relaxing normally. Although myotonia can affect any skeletal muscles, including muscles of the face and tongue, it occurs most often in the legs. Myotonia causes muscle stiffness that can interfere with movement. In some people the stiffness is very mild, while in other cases it may be severe enough to interfere with walking, running, and other activities of daily life. These muscle problems are particularly noticeable during movement following a period of rest. Many affected individuals find that repeated movements can temporarily alleviate their muscle stiffness, a phenomenon known as the warm-up effect. The two major types of myotonia congenita are known as Thomsen disease and Becker disease. These conditions are distinguished by the severity of their symptoms and their patterns of inheritance. Becker disease usually appears later in childhood than Thomsen disease and causes more severe muscle stiffness, particularly in males. People with Becker disease often experience temporary attacks of muscle weakness, particularly in the arms and hands, brought on by movement after periods of rest. They may also develop mild, permanent muscle weakness over time. This muscle weakness is not seen in people with Thomsen disease. Myotonia congenita is estimated to affect 1 in 100,000 people worldwide. This condition is more common in northern Scandinavia, where it occurs in approximately 1 in 10,000 people. Mutations in the CLCN1 gene cause myotonia congenita. The CLCN1 gene provides instructions for making a protein that is critical for the normal function of skeletal muscle cells. For the body to move normally, skeletal muscles must tense (contract) and relax in a coordinated way. Muscle contraction and relaxation are controlled by the flow of charged atoms (ions) into and out of muscle cells. Specifically, the protein produced from the CLCN1 gene forms a channel that controls the flow of negatively charged chlorine atoms (chloride ions) into these cells. The main function of this channel is to stabilize the cells' electrical charge, which prevents muscles from contracting abnormally. Mutations in the CLCN1 gene alter the usual structure or function of chloride channels. The altered channels cannot properly regulate ion flow, reducing the movement of chloride ions into skeletal muscle cells. This disruption in chloride ion flow triggers prolonged muscle contractions, which are the hallmark of myotonia. The two forms of myotonia congenita have different patterns of inheritance. Thomsen disease is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. Becker disease is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition. Because several CLCN1 mutations can cause either Becker disease or Thomsen disease, doctors usually rely on characteristic signs and symptoms to distinguish the two forms of myotonia congenita. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is myotonia congenita inherited ? | The two forms of myotonia congenita have different patterns of inheritance. Thomsen disease is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. Becker disease is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition. Because several CLCN1 mutations can cause either Becker disease or Thomsen disease, doctors usually rely on characteristic signs and symptoms to distinguish the two forms of myotonia congenita. |
Myotonia congenita is a disorder that affects muscles used for movement (skeletal muscles). Beginning in childhood, people with this condition experience bouts of sustained muscle tensing (myotonia) that prevent muscles from relaxing normally. Although myotonia can affect any skeletal muscles, including muscles of the face and tongue, it occurs most often in the legs. Myotonia causes muscle stiffness that can interfere with movement. In some people the stiffness is very mild, while in other cases it may be severe enough to interfere with walking, running, and other activities of daily life. These muscle problems are particularly noticeable during movement following a period of rest. Many affected individuals find that repeated movements can temporarily alleviate their muscle stiffness, a phenomenon known as the warm-up effect. The two major types of myotonia congenita are known as Thomsen disease and Becker disease. These conditions are distinguished by the severity of their symptoms and their patterns of inheritance. Becker disease usually appears later in childhood than Thomsen disease and causes more severe muscle stiffness, particularly in males. People with Becker disease often experience temporary attacks of muscle weakness, particularly in the arms and hands, brought on by movement after periods of rest. They may also develop mild, permanent muscle weakness over time. This muscle weakness is not seen in people with Thomsen disease. Myotonia congenita is estimated to affect 1 in 100,000 people worldwide. This condition is more common in northern Scandinavia, where it occurs in approximately 1 in 10,000 people. Mutations in the CLCN1 gene cause myotonia congenita. The CLCN1 gene provides instructions for making a protein that is critical for the normal function of skeletal muscle cells. For the body to move normally, skeletal muscles must tense (contract) and relax in a coordinated way. Muscle contraction and relaxation are controlled by the flow of charged atoms (ions) into and out of muscle cells. Specifically, the protein produced from the CLCN1 gene forms a channel that controls the flow of negatively charged chlorine atoms (chloride ions) into these cells. The main function of this channel is to stabilize the cells' electrical charge, which prevents muscles from contracting abnormally. Mutations in the CLCN1 gene alter the usual structure or function of chloride channels. The altered channels cannot properly regulate ion flow, reducing the movement of chloride ions into skeletal muscle cells. This disruption in chloride ion flow triggers prolonged muscle contractions, which are the hallmark of myotonia. The two forms of myotonia congenita have different patterns of inheritance. Thomsen disease is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. Becker disease is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition. Because several CLCN1 mutations can cause either Becker disease or Thomsen disease, doctors usually rely on characteristic signs and symptoms to distinguish the two forms of myotonia congenita. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for myotonia congenita ? | These resources address the diagnosis or management of myotonia congenita: - Gene Review: Gene Review: Myotonia Congenita - Genetic Testing Registry: Congenital myotonia, autosomal dominant form - Genetic Testing Registry: Congenital myotonia, autosomal recessive form - Genetic Testing Registry: Myotonia congenita - MedlinePlus Encyclopedia: Myotonia congenita These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Smith-Magenis syndrome is a developmental disorder that affects many parts of the body. The major features of this condition include mild to moderate intellectual disability, delayed speech and language skills, distinctive facial features, sleep disturbances, and behavioral problems. Most people with Smith-Magenis syndrome have a broad, square-shaped face with deep-set eyes, full cheeks, and a prominent lower jaw. The middle of the face and the bridge of the nose often appear flattened. The mouth tends to turn downward with a full, outward-curving upper lip. These facial differences can be subtle in early childhood, but they usually become more distinctive in later childhood and adulthood. Dental abnormalities are also common in affected individuals. Disrupted sleep patterns are characteristic of Smith-Magenis syndrome, typically beginning early in life. Affected people may be very sleepy during the day, but they have trouble falling asleep at night and awaken several times during the night and early morning. People with Smith-Magenis syndrome typically have affectionate, engaging personalities, but most also have behavioral problems. These include frequent temper tantrums and outbursts, aggression, anxiety, impulsiveness, and difficulty paying attention. Self-injury, including biting, hitting, head banging, and skin picking, is very common. Repetitive self-hugging is a behavioral trait that may be unique to Smith-Magenis syndrome. Some people with this condition also compulsively lick their fingers and flip pages of books and magazines (a behavior known as "lick and flip"). Other signs and symptoms of Smith-Magenis syndrome include short stature, abnormal curvature of the spine (scoliosis), reduced sensitivity to pain and temperature, and a hoarse voice. Some people with this disorder have ear abnormalities that lead to hearing loss. Affected individuals may have eye abnormalities that cause nearsightedness (myopia) and other vision problems. Although less common, heart and kidney defects also have been reported in people with Smith-Magenis syndrome. Smith-Magenis syndrome affects at least 1 in 25,000 individuals worldwide. However, researchers believe that many people with this condition are not diagnosed, so the true prevalence may be closer to 1 in 15,000 individuals. In most people with Smith-Magenis syndrome, the condition results from the deletion of a small piece of chromosome 17 in each cell. This deletion occurs on the short (p) arm of the chromosome at a position designated p11.2. The deleted segment most often includes approximately 3.7 million DNA building blocks (base pairs), also written as 3.7 megabases (Mb). (An extra copy of this segment causes a related condition called Potocki-Lupski syndrome.) Occasionally the deletion is larger or smaller. All of the deletions affect one of the two copies of chromosome 17 in each cell. Although the deleted region contains multiple genes, researchers believe that the loss of one particular gene, RAI1, underlies many of the characteristic features of Smith-Magenis syndrome. All of the deletions known to cause the condition contain this gene. The RAI1 gene provides instructions for making a protein that helps regulate the activity (expression) of other genes. Although most of the genes regulated by the RAI1 protein have not been identified, this protein appears to control the expression of several genes involved in daily (circadian) rhythms, such as the sleep-wake cycle. Studies suggest that the deletion leads to a reduced amount of RAI1 protein in cells, which disrupts the expression of genes that influence circadian rhythms. These changes may account for the sleep disturbances that occur with Smith-Magenis syndrome. It is unclear how a loss of one copy of the RAI1 gene leads to the other physical, mental, and behavioral problems associated with this condition. A small percentage of people with Smith-Magenis syndrome have a variant in the RAI1 gene instead of a chromosomal deletion. Although these individuals have many of the major features of the condition, they are less likely than people with a deletion to have short stature, hearing loss, and heart or kidney abnormalities. It is likely that, in people with a deletion, the loss of other genes in the deleted region accounts for these additional signs and symptoms; the role of these genes is under study. Smith-Magenis syndrome is usually not inherited. This condition typically results from a chromosomal deletion or an RAI1 gene variant that occurs during the formation of reproductive cells (eggs or sperm) or in early fetal development. Most people with Smith-Magenis syndrome have no history of the condition in their family. In a small number of cases, people with Smith-Magenis syndrome have inherited the deletion or variant from an unaffected mother who had the genetic change only in her egg cells. This phenomenon is called germline mosaicism. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) Smith-Magenis syndrome ? | Smith-Magenis syndrome is a developmental disorder that affects many parts of the body. The major features of this condition include mild to moderate intellectual disability, delayed speech and language skills, distinctive facial features, sleep disturbances, and behavioral problems. Most people with Smith-Magenis syndrome have a broad, square-shaped face with deep-set eyes, full cheeks, and a prominent lower jaw. The middle of the face and the bridge of the nose often appear flattened. The mouth tends to turn downward with a full, outward-curving upper lip. These facial differences can be subtle in early childhood, but they usually become more distinctive in later childhood and adulthood. Dental abnormalities are also common in affected individuals. Disrupted sleep patterns are characteristic of Smith-Magenis syndrome, typically beginning early in life. Affected people may be very sleepy during the day, but they have trouble falling asleep and awaken several times each night. People with Smith-Magenis syndrome have affectionate, engaging personalities, but most also have behavioral problems. These include frequent temper tantrums and outbursts, aggression, anxiety, impulsiveness, and difficulty paying attention. Self-injury, including biting, hitting, head banging, and skin picking, is very common. Repetitive self-hugging is a behavioral trait that may be unique to Smith-Magenis syndrome. People with this condition also compulsively lick their fingers and flip pages of books and magazines (a behavior known as "lick and flip"). Other signs and symptoms of Smith-Magenis syndrome include short stature, abnormal curvature of the spine (scoliosis), reduced sensitivity to pain and temperature, and a hoarse voice. Some people with this disorder have ear abnormalities that lead to hearing loss. Affected individuals may have eye abnormalities that cause nearsightedness (myopia) and other vision problems. Although less common, heart and kidney defects also have been reported in people with Smith-Magenis syndrome. |
Smith-Magenis syndrome is a developmental disorder that affects many parts of the body. The major features of this condition include mild to moderate intellectual disability, delayed speech and language skills, distinctive facial features, sleep disturbances, and behavioral problems. Most people with Smith-Magenis syndrome have a broad, square-shaped face with deep-set eyes, full cheeks, and a prominent lower jaw. The middle of the face and the bridge of the nose often appear flattened. The mouth tends to turn downward with a full, outward-curving upper lip. These facial differences can be subtle in early childhood, but they usually become more distinctive in later childhood and adulthood. Dental abnormalities are also common in affected individuals. Disrupted sleep patterns are characteristic of Smith-Magenis syndrome, typically beginning early in life. Affected people may be very sleepy during the day, but they have trouble falling asleep at night and awaken several times during the night and early morning. People with Smith-Magenis syndrome typically have affectionate, engaging personalities, but most also have behavioral problems. These include frequent temper tantrums and outbursts, aggression, anxiety, impulsiveness, and difficulty paying attention. Self-injury, including biting, hitting, head banging, and skin picking, is very common. Repetitive self-hugging is a behavioral trait that may be unique to Smith-Magenis syndrome. Some people with this condition also compulsively lick their fingers and flip pages of books and magazines (a behavior known as "lick and flip"). Other signs and symptoms of Smith-Magenis syndrome include short stature, abnormal curvature of the spine (scoliosis), reduced sensitivity to pain and temperature, and a hoarse voice. Some people with this disorder have ear abnormalities that lead to hearing loss. Affected individuals may have eye abnormalities that cause nearsightedness (myopia) and other vision problems. Although less common, heart and kidney defects also have been reported in people with Smith-Magenis syndrome. Smith-Magenis syndrome affects at least 1 in 25,000 individuals worldwide. However, researchers believe that many people with this condition are not diagnosed, so the true prevalence may be closer to 1 in 15,000 individuals. In most people with Smith-Magenis syndrome, the condition results from the deletion of a small piece of chromosome 17 in each cell. This deletion occurs on the short (p) arm of the chromosome at a position designated p11.2. The deleted segment most often includes approximately 3.7 million DNA building blocks (base pairs), also written as 3.7 megabases (Mb). (An extra copy of this segment causes a related condition called Potocki-Lupski syndrome.) Occasionally the deletion is larger or smaller. All of the deletions affect one of the two copies of chromosome 17 in each cell. Although the deleted region contains multiple genes, researchers believe that the loss of one particular gene, RAI1, underlies many of the characteristic features of Smith-Magenis syndrome. All of the deletions known to cause the condition contain this gene. The RAI1 gene provides instructions for making a protein that helps regulate the activity (expression) of other genes. Although most of the genes regulated by the RAI1 protein have not been identified, this protein appears to control the expression of several genes involved in daily (circadian) rhythms, such as the sleep-wake cycle. Studies suggest that the deletion leads to a reduced amount of RAI1 protein in cells, which disrupts the expression of genes that influence circadian rhythms. These changes may account for the sleep disturbances that occur with Smith-Magenis syndrome. It is unclear how a loss of one copy of the RAI1 gene leads to the other physical, mental, and behavioral problems associated with this condition. A small percentage of people with Smith-Magenis syndrome have a variant in the RAI1 gene instead of a chromosomal deletion. Although these individuals have many of the major features of the condition, they are less likely than people with a deletion to have short stature, hearing loss, and heart or kidney abnormalities. It is likely that, in people with a deletion, the loss of other genes in the deleted region accounts for these additional signs and symptoms; the role of these genes is under study. Smith-Magenis syndrome is usually not inherited. This condition typically results from a chromosomal deletion or an RAI1 gene variant that occurs during the formation of reproductive cells (eggs or sperm) or in early fetal development. Most people with Smith-Magenis syndrome have no history of the condition in their family. In a small number of cases, people with Smith-Magenis syndrome have inherited the deletion or variant from an unaffected mother who had the genetic change only in her egg cells. This phenomenon is called germline mosaicism. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by Smith-Magenis syndrome ? | Smith-Magenis syndrome affects at least 1 in 25,000 individuals worldwide. Researchers believe that many people with this condition are not diagnosed, however, so the true prevalence may be closer to 1 in 15,000 individuals. |
Smith-Magenis syndrome is a developmental disorder that affects many parts of the body. The major features of this condition include mild to moderate intellectual disability, delayed speech and language skills, distinctive facial features, sleep disturbances, and behavioral problems. Most people with Smith-Magenis syndrome have a broad, square-shaped face with deep-set eyes, full cheeks, and a prominent lower jaw. The middle of the face and the bridge of the nose often appear flattened. The mouth tends to turn downward with a full, outward-curving upper lip. These facial differences can be subtle in early childhood, but they usually become more distinctive in later childhood and adulthood. Dental abnormalities are also common in affected individuals. Disrupted sleep patterns are characteristic of Smith-Magenis syndrome, typically beginning early in life. Affected people may be very sleepy during the day, but they have trouble falling asleep at night and awaken several times during the night and early morning. People with Smith-Magenis syndrome typically have affectionate, engaging personalities, but most also have behavioral problems. These include frequent temper tantrums and outbursts, aggression, anxiety, impulsiveness, and difficulty paying attention. Self-injury, including biting, hitting, head banging, and skin picking, is very common. Repetitive self-hugging is a behavioral trait that may be unique to Smith-Magenis syndrome. Some people with this condition also compulsively lick their fingers and flip pages of books and magazines (a behavior known as "lick and flip"). Other signs and symptoms of Smith-Magenis syndrome include short stature, abnormal curvature of the spine (scoliosis), reduced sensitivity to pain and temperature, and a hoarse voice. Some people with this disorder have ear abnormalities that lead to hearing loss. Affected individuals may have eye abnormalities that cause nearsightedness (myopia) and other vision problems. Although less common, heart and kidney defects also have been reported in people with Smith-Magenis syndrome. Smith-Magenis syndrome affects at least 1 in 25,000 individuals worldwide. However, researchers believe that many people with this condition are not diagnosed, so the true prevalence may be closer to 1 in 15,000 individuals. In most people with Smith-Magenis syndrome, the condition results from the deletion of a small piece of chromosome 17 in each cell. This deletion occurs on the short (p) arm of the chromosome at a position designated p11.2. The deleted segment most often includes approximately 3.7 million DNA building blocks (base pairs), also written as 3.7 megabases (Mb). (An extra copy of this segment causes a related condition called Potocki-Lupski syndrome.) Occasionally the deletion is larger or smaller. All of the deletions affect one of the two copies of chromosome 17 in each cell. Although the deleted region contains multiple genes, researchers believe that the loss of one particular gene, RAI1, underlies many of the characteristic features of Smith-Magenis syndrome. All of the deletions known to cause the condition contain this gene. The RAI1 gene provides instructions for making a protein that helps regulate the activity (expression) of other genes. Although most of the genes regulated by the RAI1 protein have not been identified, this protein appears to control the expression of several genes involved in daily (circadian) rhythms, such as the sleep-wake cycle. Studies suggest that the deletion leads to a reduced amount of RAI1 protein in cells, which disrupts the expression of genes that influence circadian rhythms. These changes may account for the sleep disturbances that occur with Smith-Magenis syndrome. It is unclear how a loss of one copy of the RAI1 gene leads to the other physical, mental, and behavioral problems associated with this condition. A small percentage of people with Smith-Magenis syndrome have a variant in the RAI1 gene instead of a chromosomal deletion. Although these individuals have many of the major features of the condition, they are less likely than people with a deletion to have short stature, hearing loss, and heart or kidney abnormalities. It is likely that, in people with a deletion, the loss of other genes in the deleted region accounts for these additional signs and symptoms; the role of these genes is under study. Smith-Magenis syndrome is usually not inherited. This condition typically results from a chromosomal deletion or an RAI1 gene variant that occurs during the formation of reproductive cells (eggs or sperm) or in early fetal development. Most people with Smith-Magenis syndrome have no history of the condition in their family. In a small number of cases, people with Smith-Magenis syndrome have inherited the deletion or variant from an unaffected mother who had the genetic change only in her egg cells. This phenomenon is called germline mosaicism. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to Smith-Magenis syndrome ? | Most people with Smith-Magenis syndrome have a deletion of genetic material from a specific region of chromosome 17. Although this region contains multiple genes, researchers believe that the loss of one particular gene, RAI1, in each cell is responsible for most of the characteristic features of this condition. The loss of other genes in the deleted region may help explain why the features of Smith-Magenis syndrome vary among affected individuals. A small percentage of people with Smith-Magenis syndrome have a mutation in the RAI1 gene instead of a chromosomal deletion. Although these individuals have many of the major features of the condition, they are less likely than people with a chromosomal deletion to have short stature, hearing loss, and heart or kidney abnormalities. The RAI1 gene provides instructions for making a protein whose function is unknown. Mutations in one copy of this gene lead to the production of a nonfunctional version of the RAI1 protein or reduce the amount of this protein that is produced in cells. Researchers are uncertain how changes in this protein result in the physical, mental, and behavioral problems associated with Smith-Magenis syndrome. |
Smith-Magenis syndrome is a developmental disorder that affects many parts of the body. The major features of this condition include mild to moderate intellectual disability, delayed speech and language skills, distinctive facial features, sleep disturbances, and behavioral problems. Most people with Smith-Magenis syndrome have a broad, square-shaped face with deep-set eyes, full cheeks, and a prominent lower jaw. The middle of the face and the bridge of the nose often appear flattened. The mouth tends to turn downward with a full, outward-curving upper lip. These facial differences can be subtle in early childhood, but they usually become more distinctive in later childhood and adulthood. Dental abnormalities are also common in affected individuals. Disrupted sleep patterns are characteristic of Smith-Magenis syndrome, typically beginning early in life. Affected people may be very sleepy during the day, but they have trouble falling asleep at night and awaken several times during the night and early morning. People with Smith-Magenis syndrome typically have affectionate, engaging personalities, but most also have behavioral problems. These include frequent temper tantrums and outbursts, aggression, anxiety, impulsiveness, and difficulty paying attention. Self-injury, including biting, hitting, head banging, and skin picking, is very common. Repetitive self-hugging is a behavioral trait that may be unique to Smith-Magenis syndrome. Some people with this condition also compulsively lick their fingers and flip pages of books and magazines (a behavior known as "lick and flip"). Other signs and symptoms of Smith-Magenis syndrome include short stature, abnormal curvature of the spine (scoliosis), reduced sensitivity to pain and temperature, and a hoarse voice. Some people with this disorder have ear abnormalities that lead to hearing loss. Affected individuals may have eye abnormalities that cause nearsightedness (myopia) and other vision problems. Although less common, heart and kidney defects also have been reported in people with Smith-Magenis syndrome. Smith-Magenis syndrome affects at least 1 in 25,000 individuals worldwide. However, researchers believe that many people with this condition are not diagnosed, so the true prevalence may be closer to 1 in 15,000 individuals. In most people with Smith-Magenis syndrome, the condition results from the deletion of a small piece of chromosome 17 in each cell. This deletion occurs on the short (p) arm of the chromosome at a position designated p11.2. The deleted segment most often includes approximately 3.7 million DNA building blocks (base pairs), also written as 3.7 megabases (Mb). (An extra copy of this segment causes a related condition called Potocki-Lupski syndrome.) Occasionally the deletion is larger or smaller. All of the deletions affect one of the two copies of chromosome 17 in each cell. Although the deleted region contains multiple genes, researchers believe that the loss of one particular gene, RAI1, underlies many of the characteristic features of Smith-Magenis syndrome. All of the deletions known to cause the condition contain this gene. The RAI1 gene provides instructions for making a protein that helps regulate the activity (expression) of other genes. Although most of the genes regulated by the RAI1 protein have not been identified, this protein appears to control the expression of several genes involved in daily (circadian) rhythms, such as the sleep-wake cycle. Studies suggest that the deletion leads to a reduced amount of RAI1 protein in cells, which disrupts the expression of genes that influence circadian rhythms. These changes may account for the sleep disturbances that occur with Smith-Magenis syndrome. It is unclear how a loss of one copy of the RAI1 gene leads to the other physical, mental, and behavioral problems associated with this condition. A small percentage of people with Smith-Magenis syndrome have a variant in the RAI1 gene instead of a chromosomal deletion. Although these individuals have many of the major features of the condition, they are less likely than people with a deletion to have short stature, hearing loss, and heart or kidney abnormalities. It is likely that, in people with a deletion, the loss of other genes in the deleted region accounts for these additional signs and symptoms; the role of these genes is under study. Smith-Magenis syndrome is usually not inherited. This condition typically results from a chromosomal deletion or an RAI1 gene variant that occurs during the formation of reproductive cells (eggs or sperm) or in early fetal development. Most people with Smith-Magenis syndrome have no history of the condition in their family. In a small number of cases, people with Smith-Magenis syndrome have inherited the deletion or variant from an unaffected mother who had the genetic change only in her egg cells. This phenomenon is called germline mosaicism. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is Smith-Magenis syndrome inherited ? | Smith-Magenis syndrome is typically not inherited. This condition usually results from a genetic change that occurs during the formation of reproductive cells (eggs or sperm) or in early fetal development. Most often, people with Smith-Magenis syndrome have no history of the condition in their family. |
Smith-Magenis syndrome is a developmental disorder that affects many parts of the body. The major features of this condition include mild to moderate intellectual disability, delayed speech and language skills, distinctive facial features, sleep disturbances, and behavioral problems. Most people with Smith-Magenis syndrome have a broad, square-shaped face with deep-set eyes, full cheeks, and a prominent lower jaw. The middle of the face and the bridge of the nose often appear flattened. The mouth tends to turn downward with a full, outward-curving upper lip. These facial differences can be subtle in early childhood, but they usually become more distinctive in later childhood and adulthood. Dental abnormalities are also common in affected individuals. Disrupted sleep patterns are characteristic of Smith-Magenis syndrome, typically beginning early in life. Affected people may be very sleepy during the day, but they have trouble falling asleep at night and awaken several times during the night and early morning. People with Smith-Magenis syndrome typically have affectionate, engaging personalities, but most also have behavioral problems. These include frequent temper tantrums and outbursts, aggression, anxiety, impulsiveness, and difficulty paying attention. Self-injury, including biting, hitting, head banging, and skin picking, is very common. Repetitive self-hugging is a behavioral trait that may be unique to Smith-Magenis syndrome. Some people with this condition also compulsively lick their fingers and flip pages of books and magazines (a behavior known as "lick and flip"). Other signs and symptoms of Smith-Magenis syndrome include short stature, abnormal curvature of the spine (scoliosis), reduced sensitivity to pain and temperature, and a hoarse voice. Some people with this disorder have ear abnormalities that lead to hearing loss. Affected individuals may have eye abnormalities that cause nearsightedness (myopia) and other vision problems. Although less common, heart and kidney defects also have been reported in people with Smith-Magenis syndrome. Smith-Magenis syndrome affects at least 1 in 25,000 individuals worldwide. However, researchers believe that many people with this condition are not diagnosed, so the true prevalence may be closer to 1 in 15,000 individuals. In most people with Smith-Magenis syndrome, the condition results from the deletion of a small piece of chromosome 17 in each cell. This deletion occurs on the short (p) arm of the chromosome at a position designated p11.2. The deleted segment most often includes approximately 3.7 million DNA building blocks (base pairs), also written as 3.7 megabases (Mb). (An extra copy of this segment causes a related condition called Potocki-Lupski syndrome.) Occasionally the deletion is larger or smaller. All of the deletions affect one of the two copies of chromosome 17 in each cell. Although the deleted region contains multiple genes, researchers believe that the loss of one particular gene, RAI1, underlies many of the characteristic features of Smith-Magenis syndrome. All of the deletions known to cause the condition contain this gene. The RAI1 gene provides instructions for making a protein that helps regulate the activity (expression) of other genes. Although most of the genes regulated by the RAI1 protein have not been identified, this protein appears to control the expression of several genes involved in daily (circadian) rhythms, such as the sleep-wake cycle. Studies suggest that the deletion leads to a reduced amount of RAI1 protein in cells, which disrupts the expression of genes that influence circadian rhythms. These changes may account for the sleep disturbances that occur with Smith-Magenis syndrome. It is unclear how a loss of one copy of the RAI1 gene leads to the other physical, mental, and behavioral problems associated with this condition. A small percentage of people with Smith-Magenis syndrome have a variant in the RAI1 gene instead of a chromosomal deletion. Although these individuals have many of the major features of the condition, they are less likely than people with a deletion to have short stature, hearing loss, and heart or kidney abnormalities. It is likely that, in people with a deletion, the loss of other genes in the deleted region accounts for these additional signs and symptoms; the role of these genes is under study. Smith-Magenis syndrome is usually not inherited. This condition typically results from a chromosomal deletion or an RAI1 gene variant that occurs during the formation of reproductive cells (eggs or sperm) or in early fetal development. Most people with Smith-Magenis syndrome have no history of the condition in their family. In a small number of cases, people with Smith-Magenis syndrome have inherited the deletion or variant from an unaffected mother who had the genetic change only in her egg cells. This phenomenon is called germline mosaicism. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for Smith-Magenis syndrome ? | These resources address the diagnosis or management of Smith-Magenis syndrome: - Gene Review: Gene Review: Smith-Magenis Syndrome - Genetic Testing Registry: Smith-Magenis syndrome - MedlinePlus Encyclopedia: Intellectual Disability These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Lattice corneal dystrophy type I is an eye disorder that affects the clear, outer covering of the eye called the cornea. The cornea must remain clear for an individual to see properly; however, in lattice corneal dystrophy type I, protein clumps known as amyloid deposits cloud the cornea, which leads to vision impairment. The cornea is made up of several layers of tissue, and in lattice corneal dystrophy type I, the deposits form in the stromal layer. The amyloid deposits form as delicate, branching fibers that create a lattice pattern. Affected individuals often have recurrent corneal erosions, which are caused by separation of particular layers of the cornea from one another. Corneal erosions are very painful and can cause sensitivity to bright light (photophobia). Lattice corneal dystrophy type I is usually bilateral, which means it affects both eyes. The condition becomes apparent in childhood or adolescence and leads to vision problems by early adulthood. Lattice corneal dystrophy type I is one of the most common disorders in a group of conditions that are characterized by protein deposits in the cornea (corneal dystrophies); however, it is still a rare condition. The prevalence of lattice corneal dystrophy type I is unknown. Lattice corneal dystrophy type I is caused by mutations in the TGFBI gene. This gene provides instructions for making a protein that is found in many tissues throughout the body, including the cornea. The TGFBI protein is part of the extracellular matrix, an intricate network that forms in the spaces between cells and provides structural support to tissues. The protein is thought to play a role in the attachment of cells to one another (cell adhesion) and cell movement (migration). The TGFBI gene mutations involved in lattice corneal dystrophy type I change single protein building blocks (amino acids) in the TGFBI protein. Mutated TGFBI proteins abnormally clump together and form amyloid deposits. However, it is unclear how the changes caused by the gene mutations induce the protein to form deposits. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) lattice corneal dystrophy type I ? | Lattice corneal dystrophy type I is an eye disorder that affects the clear, outer covering of the eye called the cornea. The cornea must remain clear for an individual to see properly; however, in lattice corneal dystrophy type I, protein clumps known as amyloid deposits cloud the cornea, which leads to vision impairment. The cornea is made up of several layers of tissue, and in lattice corneal dystrophy type I, the deposits form in the stromal layer. The amyloid deposits form as delicate, branching fibers that create a lattice pattern. Affected individuals often have recurrent corneal erosions, which are caused by separation of particular layers of the cornea from one another. Corneal erosions are very painful and can cause sensitivity to bright light (photophobia). Lattice corneal dystrophy type I is usually bilateral, which means it affects both eyes. The condition becomes apparent in childhood or adolescence and leads to vision problems by early adulthood. |
Lattice corneal dystrophy type I is an eye disorder that affects the clear, outer covering of the eye called the cornea. The cornea must remain clear for an individual to see properly; however, in lattice corneal dystrophy type I, protein clumps known as amyloid deposits cloud the cornea, which leads to vision impairment. The cornea is made up of several layers of tissue, and in lattice corneal dystrophy type I, the deposits form in the stromal layer. The amyloid deposits form as delicate, branching fibers that create a lattice pattern. Affected individuals often have recurrent corneal erosions, which are caused by separation of particular layers of the cornea from one another. Corneal erosions are very painful and can cause sensitivity to bright light (photophobia). Lattice corneal dystrophy type I is usually bilateral, which means it affects both eyes. The condition becomes apparent in childhood or adolescence and leads to vision problems by early adulthood. Lattice corneal dystrophy type I is one of the most common disorders in a group of conditions that are characterized by protein deposits in the cornea (corneal dystrophies); however, it is still a rare condition. The prevalence of lattice corneal dystrophy type I is unknown. Lattice corneal dystrophy type I is caused by mutations in the TGFBI gene. This gene provides instructions for making a protein that is found in many tissues throughout the body, including the cornea. The TGFBI protein is part of the extracellular matrix, an intricate network that forms in the spaces between cells and provides structural support to tissues. The protein is thought to play a role in the attachment of cells to one another (cell adhesion) and cell movement (migration). The TGFBI gene mutations involved in lattice corneal dystrophy type I change single protein building blocks (amino acids) in the TGFBI protein. Mutated TGFBI proteins abnormally clump together and form amyloid deposits. However, it is unclear how the changes caused by the gene mutations induce the protein to form deposits. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by lattice corneal dystrophy type I ? | Lattice corneal dystrophy type I is one of the most common disorders in a group of conditions that are characterized by protein deposits in the cornea (corneal dystrophies); however, it is still a rare condition. The prevalence of lattice corneal dystrophy type I is unknown. |
Lattice corneal dystrophy type I is an eye disorder that affects the clear, outer covering of the eye called the cornea. The cornea must remain clear for an individual to see properly; however, in lattice corneal dystrophy type I, protein clumps known as amyloid deposits cloud the cornea, which leads to vision impairment. The cornea is made up of several layers of tissue, and in lattice corneal dystrophy type I, the deposits form in the stromal layer. The amyloid deposits form as delicate, branching fibers that create a lattice pattern. Affected individuals often have recurrent corneal erosions, which are caused by separation of particular layers of the cornea from one another. Corneal erosions are very painful and can cause sensitivity to bright light (photophobia). Lattice corneal dystrophy type I is usually bilateral, which means it affects both eyes. The condition becomes apparent in childhood or adolescence and leads to vision problems by early adulthood. Lattice corneal dystrophy type I is one of the most common disorders in a group of conditions that are characterized by protein deposits in the cornea (corneal dystrophies); however, it is still a rare condition. The prevalence of lattice corneal dystrophy type I is unknown. Lattice corneal dystrophy type I is caused by mutations in the TGFBI gene. This gene provides instructions for making a protein that is found in many tissues throughout the body, including the cornea. The TGFBI protein is part of the extracellular matrix, an intricate network that forms in the spaces between cells and provides structural support to tissues. The protein is thought to play a role in the attachment of cells to one another (cell adhesion) and cell movement (migration). The TGFBI gene mutations involved in lattice corneal dystrophy type I change single protein building blocks (amino acids) in the TGFBI protein. Mutated TGFBI proteins abnormally clump together and form amyloid deposits. However, it is unclear how the changes caused by the gene mutations induce the protein to form deposits. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to lattice corneal dystrophy type I ? | Lattice corneal dystrophy type I is caused by mutations in the TGFBI gene. This gene provides instructions for making a protein that is found in many tissues throughout the body, including the cornea. The TGFBI protein is part of the extracellular matrix, an intricate network that forms in the spaces between cells and provides structural support to tissues. The protein is thought to play a role in the attachment of cells to one another (cell adhesion) and cell movement (migration). The TGFBI gene mutations involved in lattice corneal dystrophy type I change single protein building blocks (amino acids) in the TGFBI protein. Mutated TGFBI proteins abnormally clump together and form amyloid deposits. However, it is unclear how the changes caused by the gene mutations induce the protein to form deposits. |
Lattice corneal dystrophy type I is an eye disorder that affects the clear, outer covering of the eye called the cornea. The cornea must remain clear for an individual to see properly; however, in lattice corneal dystrophy type I, protein clumps known as amyloid deposits cloud the cornea, which leads to vision impairment. The cornea is made up of several layers of tissue, and in lattice corneal dystrophy type I, the deposits form in the stromal layer. The amyloid deposits form as delicate, branching fibers that create a lattice pattern. Affected individuals often have recurrent corneal erosions, which are caused by separation of particular layers of the cornea from one another. Corneal erosions are very painful and can cause sensitivity to bright light (photophobia). Lattice corneal dystrophy type I is usually bilateral, which means it affects both eyes. The condition becomes apparent in childhood or adolescence and leads to vision problems by early adulthood. Lattice corneal dystrophy type I is one of the most common disorders in a group of conditions that are characterized by protein deposits in the cornea (corneal dystrophies); however, it is still a rare condition. The prevalence of lattice corneal dystrophy type I is unknown. Lattice corneal dystrophy type I is caused by mutations in the TGFBI gene. This gene provides instructions for making a protein that is found in many tissues throughout the body, including the cornea. The TGFBI protein is part of the extracellular matrix, an intricate network that forms in the spaces between cells and provides structural support to tissues. The protein is thought to play a role in the attachment of cells to one another (cell adhesion) and cell movement (migration). The TGFBI gene mutations involved in lattice corneal dystrophy type I change single protein building blocks (amino acids) in the TGFBI protein. Mutated TGFBI proteins abnormally clump together and form amyloid deposits. However, it is unclear how the changes caused by the gene mutations induce the protein to form deposits. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is lattice corneal dystrophy type I inherited ? | This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. |
Lattice corneal dystrophy type I is an eye disorder that affects the clear, outer covering of the eye called the cornea. The cornea must remain clear for an individual to see properly; however, in lattice corneal dystrophy type I, protein clumps known as amyloid deposits cloud the cornea, which leads to vision impairment. The cornea is made up of several layers of tissue, and in lattice corneal dystrophy type I, the deposits form in the stromal layer. The amyloid deposits form as delicate, branching fibers that create a lattice pattern. Affected individuals often have recurrent corneal erosions, which are caused by separation of particular layers of the cornea from one another. Corneal erosions are very painful and can cause sensitivity to bright light (photophobia). Lattice corneal dystrophy type I is usually bilateral, which means it affects both eyes. The condition becomes apparent in childhood or adolescence and leads to vision problems by early adulthood. Lattice corneal dystrophy type I is one of the most common disorders in a group of conditions that are characterized by protein deposits in the cornea (corneal dystrophies); however, it is still a rare condition. The prevalence of lattice corneal dystrophy type I is unknown. Lattice corneal dystrophy type I is caused by mutations in the TGFBI gene. This gene provides instructions for making a protein that is found in many tissues throughout the body, including the cornea. The TGFBI protein is part of the extracellular matrix, an intricate network that forms in the spaces between cells and provides structural support to tissues. The protein is thought to play a role in the attachment of cells to one another (cell adhesion) and cell movement (migration). The TGFBI gene mutations involved in lattice corneal dystrophy type I change single protein building blocks (amino acids) in the TGFBI protein. Mutated TGFBI proteins abnormally clump together and form amyloid deposits. However, it is unclear how the changes caused by the gene mutations induce the protein to form deposits. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for lattice corneal dystrophy type I ? | These resources address the diagnosis or management of lattice corneal dystrophy type I: - American Foundation for the Blind: Living with Vision Loss - Genetic Testing Registry: Lattice corneal dystrophy Type I - Merck Manual Home Health Edition: Diagnosis of Eye Disorders: Slit-Lamp Examination These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Piebaldism is a condition characterized by the absence of cells called melanocytes in certain areas of the skin and hair. Melanocytes produce the pigment melanin, which contributes to hair, eye, and skin color. The absence of melanocytes leads to patches of skin and hair that are lighter than normal. Approximately 90 percent of affected individuals have a white section of hair near their front hairline (a white forelock). The eyelashes, the eyebrows, and the skin under the forelock may also be unpigmented. People with piebaldism usually have other unpigmented patches of skin, typically appearing symmetrically on both sides of the body. There may be spots or patches of pigmented skin within or around the borders of the unpigmented areas. In most cases, the unpigmented areas are present at birth and do not increase in size or number. The unpigmented patches are at increased risk of sunburn and skin cancer related to excessive sun exposure. Some people with piebaldism are self-conscious about the appearance of the unpigmented patches, which may be more noticeable in darker-skinned people. Aside from these potential issues, this condition has no effect on the health of the affected individual. The prevalence of piebaldism is unknown. Piebaldism can be caused by mutations in the KIT and SNAI2 genes. Piebaldism may also be a feature of other conditions, such as Waardenburg syndrome; these conditions have other genetic causes and additional signs and symptoms. The KIT gene provides instructions for making a protein that is involved in signaling within cells. KIT protein signaling is important for the development of certain cell types, including melanocytes. The KIT gene mutations responsible for piebaldism lead to a nonfunctional KIT protein. The loss of KIT signaling is thought to disrupt the growth and division (proliferation) and movement (migration) of melanocytes during development, resulting in patches of skin that lack pigmentation. The SNAI2 gene (often called SLUG) provides instructions for making a protein called snail 2. Research indicates that the snail 2 protein is required during embryonic growth for the development of cells called neural crest cells. Neural crest cells migrate from the developing spinal cord to specific regions in the embryo and give rise to many tissues and cell types, including melanocytes. The snail 2 protein probably plays a role in the formation and survival of melanocytes. SNAI2 gene mutations that cause piebaldism probably reduce the production of the snail 2 protein. Shortage of the snail 2 protein may disrupt the development of melanocytes in certain areas of the skin and hair, causing the patchy loss of pigment. Piebaldism is sometimes mistaken for another condition called vitiligo, which also causes unpigmented patches of skin. People are not born with vitiligo, but acquire it later in life, and it is not caused by specific genetic mutations. For unknown reasons, in people with vitiligo the immune system appears to damage the melanocytes in the skin. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) piebaldism ? | Piebaldism is a condition characterized by the absence of cells called melanocytes in certain areas of the skin and hair. Melanocytes produce the pigment melanin, which contributes to hair, eye, and skin color. The absence of melanocytes leads to patches of skin and hair that are lighter than normal. Approximately 90 percent of affected individuals have a white section of hair near their front hairline (a white forelock). The eyelashes, the eyebrows, and the skin under the forelock may also be unpigmented. People with piebaldism usually have other unpigmented patches of skin, typically appearing symmetrically on both sides of the body. There may be spots or patches of pigmented skin within or around the borders of the unpigmented areas. In most cases, the unpigmented areas are present at birth and do not increase in size or number. The unpigmented patches are at increased risk of sunburn and skin cancer related to excessive sun exposure. Some people with piebaldism are self-conscious about the appearance of the unpigmented patches, which may be more noticeable in darker-skinned people. Aside from these potential issues, this condition has no effect on the health of the affected individual. |
Piebaldism is a condition characterized by the absence of cells called melanocytes in certain areas of the skin and hair. Melanocytes produce the pigment melanin, which contributes to hair, eye, and skin color. The absence of melanocytes leads to patches of skin and hair that are lighter than normal. Approximately 90 percent of affected individuals have a white section of hair near their front hairline (a white forelock). The eyelashes, the eyebrows, and the skin under the forelock may also be unpigmented. People with piebaldism usually have other unpigmented patches of skin, typically appearing symmetrically on both sides of the body. There may be spots or patches of pigmented skin within or around the borders of the unpigmented areas. In most cases, the unpigmented areas are present at birth and do not increase in size or number. The unpigmented patches are at increased risk of sunburn and skin cancer related to excessive sun exposure. Some people with piebaldism are self-conscious about the appearance of the unpigmented patches, which may be more noticeable in darker-skinned people. Aside from these potential issues, this condition has no effect on the health of the affected individual. The prevalence of piebaldism is unknown. Piebaldism can be caused by mutations in the KIT and SNAI2 genes. Piebaldism may also be a feature of other conditions, such as Waardenburg syndrome; these conditions have other genetic causes and additional signs and symptoms. The KIT gene provides instructions for making a protein that is involved in signaling within cells. KIT protein signaling is important for the development of certain cell types, including melanocytes. The KIT gene mutations responsible for piebaldism lead to a nonfunctional KIT protein. The loss of KIT signaling is thought to disrupt the growth and division (proliferation) and movement (migration) of melanocytes during development, resulting in patches of skin that lack pigmentation. The SNAI2 gene (often called SLUG) provides instructions for making a protein called snail 2. Research indicates that the snail 2 protein is required during embryonic growth for the development of cells called neural crest cells. Neural crest cells migrate from the developing spinal cord to specific regions in the embryo and give rise to many tissues and cell types, including melanocytes. The snail 2 protein probably plays a role in the formation and survival of melanocytes. SNAI2 gene mutations that cause piebaldism probably reduce the production of the snail 2 protein. Shortage of the snail 2 protein may disrupt the development of melanocytes in certain areas of the skin and hair, causing the patchy loss of pigment. Piebaldism is sometimes mistaken for another condition called vitiligo, which also causes unpigmented patches of skin. People are not born with vitiligo, but acquire it later in life, and it is not caused by specific genetic mutations. For unknown reasons, in people with vitiligo the immune system appears to damage the melanocytes in the skin. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by piebaldism ? | The prevalence of piebaldism is unknown. |
Piebaldism is a condition characterized by the absence of cells called melanocytes in certain areas of the skin and hair. Melanocytes produce the pigment melanin, which contributes to hair, eye, and skin color. The absence of melanocytes leads to patches of skin and hair that are lighter than normal. Approximately 90 percent of affected individuals have a white section of hair near their front hairline (a white forelock). The eyelashes, the eyebrows, and the skin under the forelock may also be unpigmented. People with piebaldism usually have other unpigmented patches of skin, typically appearing symmetrically on both sides of the body. There may be spots or patches of pigmented skin within or around the borders of the unpigmented areas. In most cases, the unpigmented areas are present at birth and do not increase in size or number. The unpigmented patches are at increased risk of sunburn and skin cancer related to excessive sun exposure. Some people with piebaldism are self-conscious about the appearance of the unpigmented patches, which may be more noticeable in darker-skinned people. Aside from these potential issues, this condition has no effect on the health of the affected individual. The prevalence of piebaldism is unknown. Piebaldism can be caused by mutations in the KIT and SNAI2 genes. Piebaldism may also be a feature of other conditions, such as Waardenburg syndrome; these conditions have other genetic causes and additional signs and symptoms. The KIT gene provides instructions for making a protein that is involved in signaling within cells. KIT protein signaling is important for the development of certain cell types, including melanocytes. The KIT gene mutations responsible for piebaldism lead to a nonfunctional KIT protein. The loss of KIT signaling is thought to disrupt the growth and division (proliferation) and movement (migration) of melanocytes during development, resulting in patches of skin that lack pigmentation. The SNAI2 gene (often called SLUG) provides instructions for making a protein called snail 2. Research indicates that the snail 2 protein is required during embryonic growth for the development of cells called neural crest cells. Neural crest cells migrate from the developing spinal cord to specific regions in the embryo and give rise to many tissues and cell types, including melanocytes. The snail 2 protein probably plays a role in the formation and survival of melanocytes. SNAI2 gene mutations that cause piebaldism probably reduce the production of the snail 2 protein. Shortage of the snail 2 protein may disrupt the development of melanocytes in certain areas of the skin and hair, causing the patchy loss of pigment. Piebaldism is sometimes mistaken for another condition called vitiligo, which also causes unpigmented patches of skin. People are not born with vitiligo, but acquire it later in life, and it is not caused by specific genetic mutations. For unknown reasons, in people with vitiligo the immune system appears to damage the melanocytes in the skin. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to piebaldism ? | Piebaldism can be caused by mutations in the KIT and SNAI2 genes. Piebaldism may also be a feature of other conditions, such as Waardenburg syndrome; these conditions have other genetic causes and additional signs and symptoms. The KIT gene provides instructions for making a protein that is involved in signaling within cells. KIT protein signaling is important for the development of certain cell types, including melanocytes. The KIT gene mutations responsible for piebaldism lead to a nonfunctional KIT protein. The loss of KIT signaling is thought to disrupt the growth and division (proliferation) and movement (migration) of melanocytes during development, resulting in patches of skin that lack pigmentation. The SNAI2 gene (often called SLUG) provides instructions for making a protein called snail 2. Research indicates that the snail 2 protein is required during embryonic growth for the development of cells called neural crest cells. Neural crest cells migrate from the developing spinal cord to specific regions in the embryo and give rise to many tissues and cell types, including melanocytes. The snail 2 protein probably plays a role in the formation and survival of melanocytes. SNAI2 gene mutations that cause piebaldism probably reduce the production of the snail 2 protein. Shortage of the snail 2 protein may disrupt the development of melanocytes in certain areas of the skin and hair, causing the patchy loss of pigment. Piebaldism is sometimes mistaken for another condition called vitiligo, which also causes unpigmented patches of skin. People are not born with vitiligo, but acquire it later in life, and it is not caused by specific genetic mutations. For unknown reasons, in people with vitiligo the immune system appears to damage the melanocytes in the skin. |
Piebaldism is a condition characterized by the absence of cells called melanocytes in certain areas of the skin and hair. Melanocytes produce the pigment melanin, which contributes to hair, eye, and skin color. The absence of melanocytes leads to patches of skin and hair that are lighter than normal. Approximately 90 percent of affected individuals have a white section of hair near their front hairline (a white forelock). The eyelashes, the eyebrows, and the skin under the forelock may also be unpigmented. People with piebaldism usually have other unpigmented patches of skin, typically appearing symmetrically on both sides of the body. There may be spots or patches of pigmented skin within or around the borders of the unpigmented areas. In most cases, the unpigmented areas are present at birth and do not increase in size or number. The unpigmented patches are at increased risk of sunburn and skin cancer related to excessive sun exposure. Some people with piebaldism are self-conscious about the appearance of the unpigmented patches, which may be more noticeable in darker-skinned people. Aside from these potential issues, this condition has no effect on the health of the affected individual. The prevalence of piebaldism is unknown. Piebaldism can be caused by mutations in the KIT and SNAI2 genes. Piebaldism may also be a feature of other conditions, such as Waardenburg syndrome; these conditions have other genetic causes and additional signs and symptoms. The KIT gene provides instructions for making a protein that is involved in signaling within cells. KIT protein signaling is important for the development of certain cell types, including melanocytes. The KIT gene mutations responsible for piebaldism lead to a nonfunctional KIT protein. The loss of KIT signaling is thought to disrupt the growth and division (proliferation) and movement (migration) of melanocytes during development, resulting in patches of skin that lack pigmentation. The SNAI2 gene (often called SLUG) provides instructions for making a protein called snail 2. Research indicates that the snail 2 protein is required during embryonic growth for the development of cells called neural crest cells. Neural crest cells migrate from the developing spinal cord to specific regions in the embryo and give rise to many tissues and cell types, including melanocytes. The snail 2 protein probably plays a role in the formation and survival of melanocytes. SNAI2 gene mutations that cause piebaldism probably reduce the production of the snail 2 protein. Shortage of the snail 2 protein may disrupt the development of melanocytes in certain areas of the skin and hair, causing the patchy loss of pigment. Piebaldism is sometimes mistaken for another condition called vitiligo, which also causes unpigmented patches of skin. People are not born with vitiligo, but acquire it later in life, and it is not caused by specific genetic mutations. For unknown reasons, in people with vitiligo the immune system appears to damage the melanocytes in the skin. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is piebaldism inherited ? | This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. |
Piebaldism is a condition characterized by the absence of cells called melanocytes in certain areas of the skin and hair. Melanocytes produce the pigment melanin, which contributes to hair, eye, and skin color. The absence of melanocytes leads to patches of skin and hair that are lighter than normal. Approximately 90 percent of affected individuals have a white section of hair near their front hairline (a white forelock). The eyelashes, the eyebrows, and the skin under the forelock may also be unpigmented. People with piebaldism usually have other unpigmented patches of skin, typically appearing symmetrically on both sides of the body. There may be spots or patches of pigmented skin within or around the borders of the unpigmented areas. In most cases, the unpigmented areas are present at birth and do not increase in size or number. The unpigmented patches are at increased risk of sunburn and skin cancer related to excessive sun exposure. Some people with piebaldism are self-conscious about the appearance of the unpigmented patches, which may be more noticeable in darker-skinned people. Aside from these potential issues, this condition has no effect on the health of the affected individual. The prevalence of piebaldism is unknown. Piebaldism can be caused by mutations in the KIT and SNAI2 genes. Piebaldism may also be a feature of other conditions, such as Waardenburg syndrome; these conditions have other genetic causes and additional signs and symptoms. The KIT gene provides instructions for making a protein that is involved in signaling within cells. KIT protein signaling is important for the development of certain cell types, including melanocytes. The KIT gene mutations responsible for piebaldism lead to a nonfunctional KIT protein. The loss of KIT signaling is thought to disrupt the growth and division (proliferation) and movement (migration) of melanocytes during development, resulting in patches of skin that lack pigmentation. The SNAI2 gene (often called SLUG) provides instructions for making a protein called snail 2. Research indicates that the snail 2 protein is required during embryonic growth for the development of cells called neural crest cells. Neural crest cells migrate from the developing spinal cord to specific regions in the embryo and give rise to many tissues and cell types, including melanocytes. The snail 2 protein probably plays a role in the formation and survival of melanocytes. SNAI2 gene mutations that cause piebaldism probably reduce the production of the snail 2 protein. Shortage of the snail 2 protein may disrupt the development of melanocytes in certain areas of the skin and hair, causing the patchy loss of pigment. Piebaldism is sometimes mistaken for another condition called vitiligo, which also causes unpigmented patches of skin. People are not born with vitiligo, but acquire it later in life, and it is not caused by specific genetic mutations. For unknown reasons, in people with vitiligo the immune system appears to damage the melanocytes in the skin. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for piebaldism ? | These resources address the diagnosis or management of piebaldism: - Genetic Testing Registry: Partial albinism These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Essential pentosuria is a condition characterized by high levels of a sugar called L-xylulose in urine. The condition is so named because L-xylulose is a type of sugar called a pentose. Despite the excess sugar, affected individuals have no associated health problems. Essential pentosuria occurs almost exclusively in individuals with Ashkenazi Jewish ancestry. Approximately 1 in 3,300 people in this population are affected. Essential pentosuria is caused by mutations in the DCXR gene. This gene provides instructions for making a protein called dicarbonyl and L-xylulose reductase (DCXR), which plays multiple roles in the body. One of its functions is to perform a chemical reaction that converts a sugar called L-xylulose to a molecule called xylitol. This reaction is one step in a process by which the body can use sugars for energy. DCXR gene mutations lead to the production of altered DCXR proteins that are quickly broken down. Without this protein, L-xylulose is not converted to xylitol, and the excess sugar is released in the urine. While essential pentosuria is caused by genetic mutations, some people develop a non-inherited form of pentosuria if they eat excessive amounts of fruits high in L-xylulose or another pentose called L-arabinose. This form of the condition, which disappears if the diet is changed, is referred to as alimentary pentosuria. Studies show that some drugs can also cause a form of temporary pentosuria called drug-induced pentosuria. These non-inherited forms of the condition also do not cause any health problems. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) essential pentosuria ? | Essential pentosuria is a condition characterized by high levels of a sugar called L-xylulose in urine. The condition is so named because L-xylulose is a type of sugar called a pentose. Despite the excess sugar, affected individuals have no associated health problems. |
Essential pentosuria is a condition characterized by high levels of a sugar called L-xylulose in urine. The condition is so named because L-xylulose is a type of sugar called a pentose. Despite the excess sugar, affected individuals have no associated health problems. Essential pentosuria occurs almost exclusively in individuals with Ashkenazi Jewish ancestry. Approximately 1 in 3,300 people in this population are affected. Essential pentosuria is caused by mutations in the DCXR gene. This gene provides instructions for making a protein called dicarbonyl and L-xylulose reductase (DCXR), which plays multiple roles in the body. One of its functions is to perform a chemical reaction that converts a sugar called L-xylulose to a molecule called xylitol. This reaction is one step in a process by which the body can use sugars for energy. DCXR gene mutations lead to the production of altered DCXR proteins that are quickly broken down. Without this protein, L-xylulose is not converted to xylitol, and the excess sugar is released in the urine. While essential pentosuria is caused by genetic mutations, some people develop a non-inherited form of pentosuria if they eat excessive amounts of fruits high in L-xylulose or another pentose called L-arabinose. This form of the condition, which disappears if the diet is changed, is referred to as alimentary pentosuria. Studies show that some drugs can also cause a form of temporary pentosuria called drug-induced pentosuria. These non-inherited forms of the condition also do not cause any health problems. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by essential pentosuria ? | Essential pentosuria occurs almost exclusively in individuals with Ashkenazi Jewish ancestry. Approximately 1 in 3,300 people in this population are affected. |
Essential pentosuria is a condition characterized by high levels of a sugar called L-xylulose in urine. The condition is so named because L-xylulose is a type of sugar called a pentose. Despite the excess sugar, affected individuals have no associated health problems. Essential pentosuria occurs almost exclusively in individuals with Ashkenazi Jewish ancestry. Approximately 1 in 3,300 people in this population are affected. Essential pentosuria is caused by mutations in the DCXR gene. This gene provides instructions for making a protein called dicarbonyl and L-xylulose reductase (DCXR), which plays multiple roles in the body. One of its functions is to perform a chemical reaction that converts a sugar called L-xylulose to a molecule called xylitol. This reaction is one step in a process by which the body can use sugars for energy. DCXR gene mutations lead to the production of altered DCXR proteins that are quickly broken down. Without this protein, L-xylulose is not converted to xylitol, and the excess sugar is released in the urine. While essential pentosuria is caused by genetic mutations, some people develop a non-inherited form of pentosuria if they eat excessive amounts of fruits high in L-xylulose or another pentose called L-arabinose. This form of the condition, which disappears if the diet is changed, is referred to as alimentary pentosuria. Studies show that some drugs can also cause a form of temporary pentosuria called drug-induced pentosuria. These non-inherited forms of the condition also do not cause any health problems. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to essential pentosuria ? | Essential pentosuria is caused by mutations in the DCXR gene. This gene provides instructions for making a protein called dicarbonyl/L-xylulose reductase (DCXR), which plays multiple roles in the body. One of its functions is to perform a chemical reaction that converts a sugar called L-xylulose to a molecule called xylitol. This reaction is one step in a process by which the body can use sugars for energy. DCXR gene mutations lead to the production of altered DCXR proteins that are quickly broken down. Without this protein, L-xylulose is not converted to xylitol, and the excess sugar is released in the urine. While essential pentosuria is caused by genetic mutations, some people develop a non-inherited form of pentosuria if they eat excessive amounts of fruits high in L-xylulose or another pentose called L-arabinose. This form of the condition, which disappears if the diet is changed, is referred to as alimentary pentosuria. Studies show that some drugs can also cause a form of temporary pentosuria called drug-induced pentosuria. These non-inherited forms of the condition also do not cause any health problems. |
Essential pentosuria is a condition characterized by high levels of a sugar called L-xylulose in urine. The condition is so named because L-xylulose is a type of sugar called a pentose. Despite the excess sugar, affected individuals have no associated health problems. Essential pentosuria occurs almost exclusively in individuals with Ashkenazi Jewish ancestry. Approximately 1 in 3,300 people in this population are affected. Essential pentosuria is caused by mutations in the DCXR gene. This gene provides instructions for making a protein called dicarbonyl and L-xylulose reductase (DCXR), which plays multiple roles in the body. One of its functions is to perform a chemical reaction that converts a sugar called L-xylulose to a molecule called xylitol. This reaction is one step in a process by which the body can use sugars for energy. DCXR gene mutations lead to the production of altered DCXR proteins that are quickly broken down. Without this protein, L-xylulose is not converted to xylitol, and the excess sugar is released in the urine. While essential pentosuria is caused by genetic mutations, some people develop a non-inherited form of pentosuria if they eat excessive amounts of fruits high in L-xylulose or another pentose called L-arabinose. This form of the condition, which disappears if the diet is changed, is referred to as alimentary pentosuria. Studies show that some drugs can also cause a form of temporary pentosuria called drug-induced pentosuria. These non-inherited forms of the condition also do not cause any health problems. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is essential pentosuria inherited ? | This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. |
Essential pentosuria is a condition characterized by high levels of a sugar called L-xylulose in urine. The condition is so named because L-xylulose is a type of sugar called a pentose. Despite the excess sugar, affected individuals have no associated health problems. Essential pentosuria occurs almost exclusively in individuals with Ashkenazi Jewish ancestry. Approximately 1 in 3,300 people in this population are affected. Essential pentosuria is caused by mutations in the DCXR gene. This gene provides instructions for making a protein called dicarbonyl and L-xylulose reductase (DCXR), which plays multiple roles in the body. One of its functions is to perform a chemical reaction that converts a sugar called L-xylulose to a molecule called xylitol. This reaction is one step in a process by which the body can use sugars for energy. DCXR gene mutations lead to the production of altered DCXR proteins that are quickly broken down. Without this protein, L-xylulose is not converted to xylitol, and the excess sugar is released in the urine. While essential pentosuria is caused by genetic mutations, some people develop a non-inherited form of pentosuria if they eat excessive amounts of fruits high in L-xylulose or another pentose called L-arabinose. This form of the condition, which disappears if the diet is changed, is referred to as alimentary pentosuria. Studies show that some drugs can also cause a form of temporary pentosuria called drug-induced pentosuria. These non-inherited forms of the condition also do not cause any health problems. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for essential pentosuria ? | These resources address the diagnosis or management of essential pentosuria: - Genetic Testing Registry: Essential pentosuria These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Melnick-Needles syndrome is a disorder involving abnormalities in skeletal development and other health problems. It is a member of a group of related conditions called otopalatodigital spectrum disorders, which also includes otopalatodigital syndrome type 1, otopalatodigital syndrome type 2, frontometaphyseal dysplasia, and terminal osseous dysplasia. In general, these disorders involve hearing loss caused by malformations in the tiny bones in the ears (ossicles), problems in the development of the roof of the mouth (palate), and skeletal abnormalities involving the fingers and/or toes (digits). Melnick-Needles syndrome is usually the most severe of the otopalatodigital spectrum disorders. People with this condition are usually of short stature, have an abnormal curvature of the spine (scoliosis), partial dislocation (subluxation) of certain joints, and unusually long fingers and toes. They may have bowed limbs; underdeveloped, irregular ribs that can cause problems with breathing; and other abnormal or absent bones. Characteristic facial features may include bulging eyes with prominent brow ridges, excess hair growth on the forehead, round cheeks, a very small lower jaw and chin (micrognathia), and misaligned teeth. One side of the face may appear noticeably different from the other (facial asymmetry). Some individuals with this disorder have hearing loss. In addition to skeletal abnormalities, individuals with Melnick-Needles syndrome may have obstruction of the ducts between the kidneys and bladder (ureters) or heart defects. Males with Melnick-Needles syndrome generally have much more severe signs and symptoms than do females, and in almost all cases die before or soon after birth. Melnick-Needles syndrome is a rare disorder; fewer than 100 cases have been reported worldwide. Variants (also called mutations) in the FLNA gene cause Melnick-Needles syndrome. The FLNA gene provides instructions for producing the protein filamin A, which helps build the network of protein filaments (cytoskeleton) that gives structure to cells and allows them to change shape and move. Filamin A binds to another protein called actin, and helps the actin to form the branching network of filaments that make up the cytoskeleton. Filamin A also links actin to many other proteins to perform various functions within the cell. A small number of variants in the FLNA gene have been identified in people with Melnick-Needles syndrome. These variants are described as "gain-of-function" because they appear to enhance the activity of the filamin A protein or give the protein a new, atypical function. Researchers believe that the variants may change the way the filamin A protein helps regulate processes involved in skeletal development, but it is not known how changes in the protein relate to the specific signs and symptoms of Melnick-Needles syndrome. This condition is inherited in an X-linked dominant pattern. The gene associated with this condition is located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a variant in one of the two copies of the gene in each cell is sufficient to cause the disorder. In males (who have only one X chromosome), a variant in the only copy of the gene in each cell causes the disorder. In most cases, males experience more severe symptoms of the disorder than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) Melnick-Needles syndrome ? | Melnick-Needles syndrome is a disorder involving abnormalities in skeletal development and other health problems. It is a member of a group of related conditions called otopalatodigital spectrum disorders, which also includes otopalatodigital syndrome type 1, otopalatodigital syndrome type 2, and frontometaphyseal dysplasia. In general, these disorders involve hearing loss caused by malformations in the tiny bones in the ears (ossicles), problems in the development of the roof of the mouth (palate), and skeletal abnormalities involving the fingers and/or toes (digits). Melnick-Needles syndrome is usually the most severe of the otopalatodigital spectrum disorders. People with this condition are usually of short stature, have an abnormal curvature of the spine (scoliosis), partial dislocation (subluxation) of certain joints, and unusually long fingers and toes. They may have bowed limbs; underdeveloped, irregular ribs that can cause problems with breathing; and other abnormal or absent bones. Characteristic facial features may include bulging eyes with prominent brow ridges, excess hair growth on the forehead, round cheeks, a very small lower jaw and chin (micrognathia), and misaligned teeth. One side of the face may appear noticeably different from the other (facial asymmetry). Some individuals with this disorder have hearing loss. In addition to skeletal abnormalities, individuals with Melnick-Needles syndrome may have obstruction of the ducts between the kidneys and bladder (ureters) or heart defects. Males with Melnick-Needles syndrome generally have much more severe signs and symptoms than do females, and in almost all cases die before or soon after birth. |
Melnick-Needles syndrome is a disorder involving abnormalities in skeletal development and other health problems. It is a member of a group of related conditions called otopalatodigital spectrum disorders, which also includes otopalatodigital syndrome type 1, otopalatodigital syndrome type 2, frontometaphyseal dysplasia, and terminal osseous dysplasia. In general, these disorders involve hearing loss caused by malformations in the tiny bones in the ears (ossicles), problems in the development of the roof of the mouth (palate), and skeletal abnormalities involving the fingers and/or toes (digits). Melnick-Needles syndrome is usually the most severe of the otopalatodigital spectrum disorders. People with this condition are usually of short stature, have an abnormal curvature of the spine (scoliosis), partial dislocation (subluxation) of certain joints, and unusually long fingers and toes. They may have bowed limbs; underdeveloped, irregular ribs that can cause problems with breathing; and other abnormal or absent bones. Characteristic facial features may include bulging eyes with prominent brow ridges, excess hair growth on the forehead, round cheeks, a very small lower jaw and chin (micrognathia), and misaligned teeth. One side of the face may appear noticeably different from the other (facial asymmetry). Some individuals with this disorder have hearing loss. In addition to skeletal abnormalities, individuals with Melnick-Needles syndrome may have obstruction of the ducts between the kidneys and bladder (ureters) or heart defects. Males with Melnick-Needles syndrome generally have much more severe signs and symptoms than do females, and in almost all cases die before or soon after birth. Melnick-Needles syndrome is a rare disorder; fewer than 100 cases have been reported worldwide. Variants (also called mutations) in the FLNA gene cause Melnick-Needles syndrome. The FLNA gene provides instructions for producing the protein filamin A, which helps build the network of protein filaments (cytoskeleton) that gives structure to cells and allows them to change shape and move. Filamin A binds to another protein called actin, and helps the actin to form the branching network of filaments that make up the cytoskeleton. Filamin A also links actin to many other proteins to perform various functions within the cell. A small number of variants in the FLNA gene have been identified in people with Melnick-Needles syndrome. These variants are described as "gain-of-function" because they appear to enhance the activity of the filamin A protein or give the protein a new, atypical function. Researchers believe that the variants may change the way the filamin A protein helps regulate processes involved in skeletal development, but it is not known how changes in the protein relate to the specific signs and symptoms of Melnick-Needles syndrome. This condition is inherited in an X-linked dominant pattern. The gene associated with this condition is located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a variant in one of the two copies of the gene in each cell is sufficient to cause the disorder. In males (who have only one X chromosome), a variant in the only copy of the gene in each cell causes the disorder. In most cases, males experience more severe symptoms of the disorder than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by Melnick-Needles syndrome ? | Melnick-Needles syndrome is a rare disorder; fewer than 100 cases have been reported worldwide. |
Melnick-Needles syndrome is a disorder involving abnormalities in skeletal development and other health problems. It is a member of a group of related conditions called otopalatodigital spectrum disorders, which also includes otopalatodigital syndrome type 1, otopalatodigital syndrome type 2, frontometaphyseal dysplasia, and terminal osseous dysplasia. In general, these disorders involve hearing loss caused by malformations in the tiny bones in the ears (ossicles), problems in the development of the roof of the mouth (palate), and skeletal abnormalities involving the fingers and/or toes (digits). Melnick-Needles syndrome is usually the most severe of the otopalatodigital spectrum disorders. People with this condition are usually of short stature, have an abnormal curvature of the spine (scoliosis), partial dislocation (subluxation) of certain joints, and unusually long fingers and toes. They may have bowed limbs; underdeveloped, irregular ribs that can cause problems with breathing; and other abnormal or absent bones. Characteristic facial features may include bulging eyes with prominent brow ridges, excess hair growth on the forehead, round cheeks, a very small lower jaw and chin (micrognathia), and misaligned teeth. One side of the face may appear noticeably different from the other (facial asymmetry). Some individuals with this disorder have hearing loss. In addition to skeletal abnormalities, individuals with Melnick-Needles syndrome may have obstruction of the ducts between the kidneys and bladder (ureters) or heart defects. Males with Melnick-Needles syndrome generally have much more severe signs and symptoms than do females, and in almost all cases die before or soon after birth. Melnick-Needles syndrome is a rare disorder; fewer than 100 cases have been reported worldwide. Variants (also called mutations) in the FLNA gene cause Melnick-Needles syndrome. The FLNA gene provides instructions for producing the protein filamin A, which helps build the network of protein filaments (cytoskeleton) that gives structure to cells and allows them to change shape and move. Filamin A binds to another protein called actin, and helps the actin to form the branching network of filaments that make up the cytoskeleton. Filamin A also links actin to many other proteins to perform various functions within the cell. A small number of variants in the FLNA gene have been identified in people with Melnick-Needles syndrome. These variants are described as "gain-of-function" because they appear to enhance the activity of the filamin A protein or give the protein a new, atypical function. Researchers believe that the variants may change the way the filamin A protein helps regulate processes involved in skeletal development, but it is not known how changes in the protein relate to the specific signs and symptoms of Melnick-Needles syndrome. This condition is inherited in an X-linked dominant pattern. The gene associated with this condition is located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a variant in one of the two copies of the gene in each cell is sufficient to cause the disorder. In males (who have only one X chromosome), a variant in the only copy of the gene in each cell causes the disorder. In most cases, males experience more severe symptoms of the disorder than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to Melnick-Needles syndrome ? | Mutations in the FLNA gene cause Melnick-Needles syndrome. The FLNA gene provides instructions for producing the protein filamin A, which helps build the network of protein filaments (cytoskeleton) that gives structure to cells and allows them to change shape and move. Filamin A binds to another protein called actin, and helps the actin to form the branching network of filaments that make up the cytoskeleton. Filamin A also links actin to many other proteins to perform various functions within the cell. A small number of mutations in the FLNA gene have been identified in people with Melnick-Needles syndrome. These mutations are described as "gain-of-function" because they appear to enhance the activity of the filamin A protein or give the protein a new, atypical function. Researchers believe that the mutations may change the way the filamin A protein helps regulate processes involved in skeletal development, but it is not known how changes in the protein relate to the specific signs and symptoms of Melnick-Needles syndrome. |
Melnick-Needles syndrome is a disorder involving abnormalities in skeletal development and other health problems. It is a member of a group of related conditions called otopalatodigital spectrum disorders, which also includes otopalatodigital syndrome type 1, otopalatodigital syndrome type 2, frontometaphyseal dysplasia, and terminal osseous dysplasia. In general, these disorders involve hearing loss caused by malformations in the tiny bones in the ears (ossicles), problems in the development of the roof of the mouth (palate), and skeletal abnormalities involving the fingers and/or toes (digits). Melnick-Needles syndrome is usually the most severe of the otopalatodigital spectrum disorders. People with this condition are usually of short stature, have an abnormal curvature of the spine (scoliosis), partial dislocation (subluxation) of certain joints, and unusually long fingers and toes. They may have bowed limbs; underdeveloped, irregular ribs that can cause problems with breathing; and other abnormal or absent bones. Characteristic facial features may include bulging eyes with prominent brow ridges, excess hair growth on the forehead, round cheeks, a very small lower jaw and chin (micrognathia), and misaligned teeth. One side of the face may appear noticeably different from the other (facial asymmetry). Some individuals with this disorder have hearing loss. In addition to skeletal abnormalities, individuals with Melnick-Needles syndrome may have obstruction of the ducts between the kidneys and bladder (ureters) or heart defects. Males with Melnick-Needles syndrome generally have much more severe signs and symptoms than do females, and in almost all cases die before or soon after birth. Melnick-Needles syndrome is a rare disorder; fewer than 100 cases have been reported worldwide. Variants (also called mutations) in the FLNA gene cause Melnick-Needles syndrome. The FLNA gene provides instructions for producing the protein filamin A, which helps build the network of protein filaments (cytoskeleton) that gives structure to cells and allows them to change shape and move. Filamin A binds to another protein called actin, and helps the actin to form the branching network of filaments that make up the cytoskeleton. Filamin A also links actin to many other proteins to perform various functions within the cell. A small number of variants in the FLNA gene have been identified in people with Melnick-Needles syndrome. These variants are described as "gain-of-function" because they appear to enhance the activity of the filamin A protein or give the protein a new, atypical function. Researchers believe that the variants may change the way the filamin A protein helps regulate processes involved in skeletal development, but it is not known how changes in the protein relate to the specific signs and symptoms of Melnick-Needles syndrome. This condition is inherited in an X-linked dominant pattern. The gene associated with this condition is located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a variant in one of the two copies of the gene in each cell is sufficient to cause the disorder. In males (who have only one X chromosome), a variant in the only copy of the gene in each cell causes the disorder. In most cases, males experience more severe symptoms of the disorder than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is Melnick-Needles syndrome inherited ? | This condition is inherited in an X-linked dominant pattern. The gene associated with this condition is located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a mutation in one of the two copies of the gene in each cell is sufficient to cause the disorder. In males (who have only one X chromosome), a mutation in the only copy of the gene in each cell causes the disorder. In most cases, males experience more severe symptoms of the disorder than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. |
Melnick-Needles syndrome is a disorder involving abnormalities in skeletal development and other health problems. It is a member of a group of related conditions called otopalatodigital spectrum disorders, which also includes otopalatodigital syndrome type 1, otopalatodigital syndrome type 2, frontometaphyseal dysplasia, and terminal osseous dysplasia. In general, these disorders involve hearing loss caused by malformations in the tiny bones in the ears (ossicles), problems in the development of the roof of the mouth (palate), and skeletal abnormalities involving the fingers and/or toes (digits). Melnick-Needles syndrome is usually the most severe of the otopalatodigital spectrum disorders. People with this condition are usually of short stature, have an abnormal curvature of the spine (scoliosis), partial dislocation (subluxation) of certain joints, and unusually long fingers and toes. They may have bowed limbs; underdeveloped, irregular ribs that can cause problems with breathing; and other abnormal or absent bones. Characteristic facial features may include bulging eyes with prominent brow ridges, excess hair growth on the forehead, round cheeks, a very small lower jaw and chin (micrognathia), and misaligned teeth. One side of the face may appear noticeably different from the other (facial asymmetry). Some individuals with this disorder have hearing loss. In addition to skeletal abnormalities, individuals with Melnick-Needles syndrome may have obstruction of the ducts between the kidneys and bladder (ureters) or heart defects. Males with Melnick-Needles syndrome generally have much more severe signs and symptoms than do females, and in almost all cases die before or soon after birth. Melnick-Needles syndrome is a rare disorder; fewer than 100 cases have been reported worldwide. Variants (also called mutations) in the FLNA gene cause Melnick-Needles syndrome. The FLNA gene provides instructions for producing the protein filamin A, which helps build the network of protein filaments (cytoskeleton) that gives structure to cells and allows them to change shape and move. Filamin A binds to another protein called actin, and helps the actin to form the branching network of filaments that make up the cytoskeleton. Filamin A also links actin to many other proteins to perform various functions within the cell. A small number of variants in the FLNA gene have been identified in people with Melnick-Needles syndrome. These variants are described as "gain-of-function" because they appear to enhance the activity of the filamin A protein or give the protein a new, atypical function. Researchers believe that the variants may change the way the filamin A protein helps regulate processes involved in skeletal development, but it is not known how changes in the protein relate to the specific signs and symptoms of Melnick-Needles syndrome. This condition is inherited in an X-linked dominant pattern. The gene associated with this condition is located on the X chromosome, which is one of the two sex chromosomes. In females (who have two X chromosomes), a variant in one of the two copies of the gene in each cell is sufficient to cause the disorder. In males (who have only one X chromosome), a variant in the only copy of the gene in each cell causes the disorder. In most cases, males experience more severe symptoms of the disorder than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for Melnick-Needles syndrome ? | These resources address the diagnosis or management of Melnick-Needles syndrome: - Gene Review: Gene Review: Otopalatodigital Spectrum Disorders - Genetic Testing Registry: Melnick-Needles syndrome These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Lactose intolerance is an impaired ability to digest lactose, a sugar found in milk and other dairy products. Lactose is normally broken down by an enzyme called lactase, which is produced by cells in the lining of the small intestine. Congenital lactase deficiency, also called congenital alactasia, is a disorder in which infants are unable to break down lactose in breast milk or formula. This form of lactose intolerance results in severe diarrhea. If affected infants are not given a lactose-free infant formula, they may develop severe dehydration and weight loss. Lactose intolerance in adulthood is caused by reduced production of lactase after infancy (lactase nonpersistence). If individuals with lactose intolerance consume lactose-containing dairy products, they may experience abdominal pain, bloating, flatulence, nausea, and diarrhea beginning 30 minutes to 2 hours later. Most people with lactase nonpersistence retain some lactase activity and can include varying amounts of lactose in their diets without experiencing symptoms. Often, affected individuals have difficulty digesting fresh milk but can eat certain dairy products such as cheese or yogurt without discomfort. These foods are made using fermentation processes that break down much of the lactose in milk. Lactose intolerance in infancy resulting from congenital lactase deficiency is a rare disorder. Its incidence is unknown. This condition is most common in Finland, where it affects an estimated 1 in 60,000 newborns. Approximately 65 percent of the human population has a reduced ability to digest lactose after infancy. Lactose intolerance in adulthood is most prevalent in people of East Asian descent, with 70 to 100 percent of people affected in these communities. Lactose intolerance is also very common in people of West African, Arab, Jewish, Greek, and Italian descent. The prevalence of lactose intolerance is lowest in populations with a long history of dependence on unfermented milk products as an important food source. For example, only about 5 percent of people of Northern European descent are lactose intolerant. Lactose intolerance in infants (congenital lactase deficiency) is caused by mutations in the LCT gene. The LCT gene provides instructions for making the lactase enzyme. Mutations that cause congenital lactase deficiency are believed to interfere with the function of lactase, causing affected infants to have a severely impaired ability to digest lactose in breast milk or formula. Lactose intolerance in adulthood is caused by gradually decreasing activity (expression) of the LCT gene after infancy, which occurs in most humans. LCT gene expression is controlled by a DNA sequence called a regulatory element, which is located within a nearby gene called MCM6. Some individuals have inherited changes in this element that lead to sustained lactase production in the small intestine and the ability to digest lactose throughout life. People without these changes have a reduced ability to digest lactose as they get older, resulting in the signs and symptoms of lactose intolerance. The type of lactose intolerance that occurs in infants (congenital lactase deficiency) is inherited in an autosomal recessive pattern, which means both copies of the LCT gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The ability to digest lactose into adulthood depends on which variations in the regulatory element within the MCM6 gene individuals have inherited from their parents. The variations that promote continued lactase production are considered autosomal dominant, which means one copy of the altered regulatory element in each cell is sufficient to sustain lactase production. People who have not inherited these variations from either parent will have some degree of lactose intolerance. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) lactose intolerance ? | Lactose intolerance is an impaired ability to digest lactose, a sugar found in milk and other dairy products. Lactose is normally broken down by an enzyme called lactase, which is produced by cells in the lining of the small intestine. Congenital lactase deficiency, also called congenital alactasia, is a disorder in which infants are unable to break down lactose in breast milk or formula. This form of lactose intolerance results in severe diarrhea. If affected infants are not given a lactose-free infant formula, they may develop severe dehydration and weight loss. Lactose intolerance in adulthood is caused by reduced production of lactase after infancy (lactase nonpersistence). If individuals with lactose intolerance consume lactose-containing dairy products, they may experience abdominal pain, bloating, flatulence, nausea, and diarrhea beginning 30 minutes to 2 hours later. Most people with lactase nonpersistence retain some lactase activity and can include varying amounts of lactose in their diets without experiencing symptoms. Often, affected individuals have difficulty digesting fresh milk but can eat certain dairy products such as cheese or yogurt without discomfort. These foods are made using fermentation processes that break down much of the lactose in milk. |
Lactose intolerance is an impaired ability to digest lactose, a sugar found in milk and other dairy products. Lactose is normally broken down by an enzyme called lactase, which is produced by cells in the lining of the small intestine. Congenital lactase deficiency, also called congenital alactasia, is a disorder in which infants are unable to break down lactose in breast milk or formula. This form of lactose intolerance results in severe diarrhea. If affected infants are not given a lactose-free infant formula, they may develop severe dehydration and weight loss. Lactose intolerance in adulthood is caused by reduced production of lactase after infancy (lactase nonpersistence). If individuals with lactose intolerance consume lactose-containing dairy products, they may experience abdominal pain, bloating, flatulence, nausea, and diarrhea beginning 30 minutes to 2 hours later. Most people with lactase nonpersistence retain some lactase activity and can include varying amounts of lactose in their diets without experiencing symptoms. Often, affected individuals have difficulty digesting fresh milk but can eat certain dairy products such as cheese or yogurt without discomfort. These foods are made using fermentation processes that break down much of the lactose in milk. Lactose intolerance in infancy resulting from congenital lactase deficiency is a rare disorder. Its incidence is unknown. This condition is most common in Finland, where it affects an estimated 1 in 60,000 newborns. Approximately 65 percent of the human population has a reduced ability to digest lactose after infancy. Lactose intolerance in adulthood is most prevalent in people of East Asian descent, with 70 to 100 percent of people affected in these communities. Lactose intolerance is also very common in people of West African, Arab, Jewish, Greek, and Italian descent. The prevalence of lactose intolerance is lowest in populations with a long history of dependence on unfermented milk products as an important food source. For example, only about 5 percent of people of Northern European descent are lactose intolerant. Lactose intolerance in infants (congenital lactase deficiency) is caused by mutations in the LCT gene. The LCT gene provides instructions for making the lactase enzyme. Mutations that cause congenital lactase deficiency are believed to interfere with the function of lactase, causing affected infants to have a severely impaired ability to digest lactose in breast milk or formula. Lactose intolerance in adulthood is caused by gradually decreasing activity (expression) of the LCT gene after infancy, which occurs in most humans. LCT gene expression is controlled by a DNA sequence called a regulatory element, which is located within a nearby gene called MCM6. Some individuals have inherited changes in this element that lead to sustained lactase production in the small intestine and the ability to digest lactose throughout life. People without these changes have a reduced ability to digest lactose as they get older, resulting in the signs and symptoms of lactose intolerance. The type of lactose intolerance that occurs in infants (congenital lactase deficiency) is inherited in an autosomal recessive pattern, which means both copies of the LCT gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The ability to digest lactose into adulthood depends on which variations in the regulatory element within the MCM6 gene individuals have inherited from their parents. The variations that promote continued lactase production are considered autosomal dominant, which means one copy of the altered regulatory element in each cell is sufficient to sustain lactase production. People who have not inherited these variations from either parent will have some degree of lactose intolerance. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by lactose intolerance ? | Lactose intolerance in infancy resulting from congenital lactase deficiency is a rare disorder. Its incidence is unknown. This condition is most common in Finland, where it affects an estimated 1 in 60,000 newborns. Approximately 65 percent of the human population has a reduced ability to digest lactose after infancy. Lactose intolerance in adulthood is most prevalent in people of East Asian descent, affecting more than 90 percent of adults in some of these communities. Lactose intolerance is also very common in people of West African, Arab, Jewish, Greek, and Italian descent. The prevalence of lactose intolerance is lowest in populations with a long history of dependence on unfermented milk products as an important food source. For example, only about 5 percent of people of Northern European descent are lactose intolerant. |
Lactose intolerance is an impaired ability to digest lactose, a sugar found in milk and other dairy products. Lactose is normally broken down by an enzyme called lactase, which is produced by cells in the lining of the small intestine. Congenital lactase deficiency, also called congenital alactasia, is a disorder in which infants are unable to break down lactose in breast milk or formula. This form of lactose intolerance results in severe diarrhea. If affected infants are not given a lactose-free infant formula, they may develop severe dehydration and weight loss. Lactose intolerance in adulthood is caused by reduced production of lactase after infancy (lactase nonpersistence). If individuals with lactose intolerance consume lactose-containing dairy products, they may experience abdominal pain, bloating, flatulence, nausea, and diarrhea beginning 30 minutes to 2 hours later. Most people with lactase nonpersistence retain some lactase activity and can include varying amounts of lactose in their diets without experiencing symptoms. Often, affected individuals have difficulty digesting fresh milk but can eat certain dairy products such as cheese or yogurt without discomfort. These foods are made using fermentation processes that break down much of the lactose in milk. Lactose intolerance in infancy resulting from congenital lactase deficiency is a rare disorder. Its incidence is unknown. This condition is most common in Finland, where it affects an estimated 1 in 60,000 newborns. Approximately 65 percent of the human population has a reduced ability to digest lactose after infancy. Lactose intolerance in adulthood is most prevalent in people of East Asian descent, with 70 to 100 percent of people affected in these communities. Lactose intolerance is also very common in people of West African, Arab, Jewish, Greek, and Italian descent. The prevalence of lactose intolerance is lowest in populations with a long history of dependence on unfermented milk products as an important food source. For example, only about 5 percent of people of Northern European descent are lactose intolerant. Lactose intolerance in infants (congenital lactase deficiency) is caused by mutations in the LCT gene. The LCT gene provides instructions for making the lactase enzyme. Mutations that cause congenital lactase deficiency are believed to interfere with the function of lactase, causing affected infants to have a severely impaired ability to digest lactose in breast milk or formula. Lactose intolerance in adulthood is caused by gradually decreasing activity (expression) of the LCT gene after infancy, which occurs in most humans. LCT gene expression is controlled by a DNA sequence called a regulatory element, which is located within a nearby gene called MCM6. Some individuals have inherited changes in this element that lead to sustained lactase production in the small intestine and the ability to digest lactose throughout life. People without these changes have a reduced ability to digest lactose as they get older, resulting in the signs and symptoms of lactose intolerance. The type of lactose intolerance that occurs in infants (congenital lactase deficiency) is inherited in an autosomal recessive pattern, which means both copies of the LCT gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The ability to digest lactose into adulthood depends on which variations in the regulatory element within the MCM6 gene individuals have inherited from their parents. The variations that promote continued lactase production are considered autosomal dominant, which means one copy of the altered regulatory element in each cell is sufficient to sustain lactase production. People who have not inherited these variations from either parent will have some degree of lactose intolerance. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to lactose intolerance ? | Lactose intolerance in infants (congenital lactase deficiency) is caused by mutations in the LCT gene. The LCT gene provides instructions for making the lactase enzyme. Mutations that cause congenital lactase deficiency are believed to interfere with the function of lactase, causing affected infants to have a severely impaired ability to digest lactose in breast milk or formula. Lactose intolerance in adulthood is caused by gradually decreasing activity (expression) of the LCT gene after infancy, which occurs in most humans. LCT gene expression is controlled by a DNA sequence called a regulatory element, which is located within a nearby gene called MCM6. Some individuals have inherited changes in this element that lead to sustained lactase production in the small intestine and the ability to digest lactose throughout life. People without these changes have a reduced ability to digest lactose as they get older, resulting in the signs and symptoms of lactose intolerance. |
Lactose intolerance is an impaired ability to digest lactose, a sugar found in milk and other dairy products. Lactose is normally broken down by an enzyme called lactase, which is produced by cells in the lining of the small intestine. Congenital lactase deficiency, also called congenital alactasia, is a disorder in which infants are unable to break down lactose in breast milk or formula. This form of lactose intolerance results in severe diarrhea. If affected infants are not given a lactose-free infant formula, they may develop severe dehydration and weight loss. Lactose intolerance in adulthood is caused by reduced production of lactase after infancy (lactase nonpersistence). If individuals with lactose intolerance consume lactose-containing dairy products, they may experience abdominal pain, bloating, flatulence, nausea, and diarrhea beginning 30 minutes to 2 hours later. Most people with lactase nonpersistence retain some lactase activity and can include varying amounts of lactose in their diets without experiencing symptoms. Often, affected individuals have difficulty digesting fresh milk but can eat certain dairy products such as cheese or yogurt without discomfort. These foods are made using fermentation processes that break down much of the lactose in milk. Lactose intolerance in infancy resulting from congenital lactase deficiency is a rare disorder. Its incidence is unknown. This condition is most common in Finland, where it affects an estimated 1 in 60,000 newborns. Approximately 65 percent of the human population has a reduced ability to digest lactose after infancy. Lactose intolerance in adulthood is most prevalent in people of East Asian descent, with 70 to 100 percent of people affected in these communities. Lactose intolerance is also very common in people of West African, Arab, Jewish, Greek, and Italian descent. The prevalence of lactose intolerance is lowest in populations with a long history of dependence on unfermented milk products as an important food source. For example, only about 5 percent of people of Northern European descent are lactose intolerant. Lactose intolerance in infants (congenital lactase deficiency) is caused by mutations in the LCT gene. The LCT gene provides instructions for making the lactase enzyme. Mutations that cause congenital lactase deficiency are believed to interfere with the function of lactase, causing affected infants to have a severely impaired ability to digest lactose in breast milk or formula. Lactose intolerance in adulthood is caused by gradually decreasing activity (expression) of the LCT gene after infancy, which occurs in most humans. LCT gene expression is controlled by a DNA sequence called a regulatory element, which is located within a nearby gene called MCM6. Some individuals have inherited changes in this element that lead to sustained lactase production in the small intestine and the ability to digest lactose throughout life. People without these changes have a reduced ability to digest lactose as they get older, resulting in the signs and symptoms of lactose intolerance. The type of lactose intolerance that occurs in infants (congenital lactase deficiency) is inherited in an autosomal recessive pattern, which means both copies of the LCT gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The ability to digest lactose into adulthood depends on which variations in the regulatory element within the MCM6 gene individuals have inherited from their parents. The variations that promote continued lactase production are considered autosomal dominant, which means one copy of the altered regulatory element in each cell is sufficient to sustain lactase production. People who have not inherited these variations from either parent will have some degree of lactose intolerance. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is lactose intolerance inherited ? | The type of lactose intolerance that occurs in infants (congenital lactase deficiency) is inherited in an autosomal recessive pattern, which means both copies of the LCT gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The ability to digest lactose into adulthood depends on which variations in the regulatory element within the MCM6 gene individuals have inherited from their parents. The variations that promote continued lactase production are considered autosomal dominant, which means one copy of the altered regulatory element in each cell is sufficient to sustain lactase production. People who have not inherited these variations from either parent will have some degree of lactose intolerance. |
Lactose intolerance is an impaired ability to digest lactose, a sugar found in milk and other dairy products. Lactose is normally broken down by an enzyme called lactase, which is produced by cells in the lining of the small intestine. Congenital lactase deficiency, also called congenital alactasia, is a disorder in which infants are unable to break down lactose in breast milk or formula. This form of lactose intolerance results in severe diarrhea. If affected infants are not given a lactose-free infant formula, they may develop severe dehydration and weight loss. Lactose intolerance in adulthood is caused by reduced production of lactase after infancy (lactase nonpersistence). If individuals with lactose intolerance consume lactose-containing dairy products, they may experience abdominal pain, bloating, flatulence, nausea, and diarrhea beginning 30 minutes to 2 hours later. Most people with lactase nonpersistence retain some lactase activity and can include varying amounts of lactose in their diets without experiencing symptoms. Often, affected individuals have difficulty digesting fresh milk but can eat certain dairy products such as cheese or yogurt without discomfort. These foods are made using fermentation processes that break down much of the lactose in milk. Lactose intolerance in infancy resulting from congenital lactase deficiency is a rare disorder. Its incidence is unknown. This condition is most common in Finland, where it affects an estimated 1 in 60,000 newborns. Approximately 65 percent of the human population has a reduced ability to digest lactose after infancy. Lactose intolerance in adulthood is most prevalent in people of East Asian descent, with 70 to 100 percent of people affected in these communities. Lactose intolerance is also very common in people of West African, Arab, Jewish, Greek, and Italian descent. The prevalence of lactose intolerance is lowest in populations with a long history of dependence on unfermented milk products as an important food source. For example, only about 5 percent of people of Northern European descent are lactose intolerant. Lactose intolerance in infants (congenital lactase deficiency) is caused by mutations in the LCT gene. The LCT gene provides instructions for making the lactase enzyme. Mutations that cause congenital lactase deficiency are believed to interfere with the function of lactase, causing affected infants to have a severely impaired ability to digest lactose in breast milk or formula. Lactose intolerance in adulthood is caused by gradually decreasing activity (expression) of the LCT gene after infancy, which occurs in most humans. LCT gene expression is controlled by a DNA sequence called a regulatory element, which is located within a nearby gene called MCM6. Some individuals have inherited changes in this element that lead to sustained lactase production in the small intestine and the ability to digest lactose throughout life. People without these changes have a reduced ability to digest lactose as they get older, resulting in the signs and symptoms of lactose intolerance. The type of lactose intolerance that occurs in infants (congenital lactase deficiency) is inherited in an autosomal recessive pattern, which means both copies of the LCT gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The ability to digest lactose into adulthood depends on which variations in the regulatory element within the MCM6 gene individuals have inherited from their parents. The variations that promote continued lactase production are considered autosomal dominant, which means one copy of the altered regulatory element in each cell is sufficient to sustain lactase production. People who have not inherited these variations from either parent will have some degree of lactose intolerance. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for lactose intolerance ? | These resources address the diagnosis or management of lactose intolerance: - Genetic Testing Registry: Congenital lactase deficiency - Genetic Testing Registry: Nonpersistence of intestinal lactase - MedlinePlus Encyclopedia: Lactose Intolerance - MedlinePlus Encyclopedia: Lactose Tolerance Tests These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Geleophysic dysplasia is an inherited condition that affects many parts of the body. It is characterized by abnormalities involving the bones, joints, heart, and skin. People with geleophysic dysplasia have short stature with very short hands and feet. Most also develop thickened skin and joint deformities called contractures, both of which significantly limit mobility. Affected individuals usually have a limited range of motion in their fingers, toes, wrists, and elbows. Additionally, contractures in the legs and hips cause many affected people to walk on their toes. The name of this condition, which comes from the Greek words for happy ("gelios") and nature ("physis"), is derived from the good-natured facial appearance seen in most affected individuals. The distinctive facial features associated with this condition include a round face with full cheeks, a small nose with upturned nostrils, a broad nasal bridge, a thin upper lip, upturned corners of the mouth, and a flat area between the upper lip and the nose (philtrum). Geleophysic dysplasia is also characterized by heart (cardiac) problems, particularly abnormalities of the cardiac valves. These valves normally control the flow of blood through the heart. In people with geleophysic dysplasia, the cardiac valves thicken, which impedes blood flow and increases blood pressure in the heart. Other heart problems have also been reported in people with geleophysic dysplasia; these include a narrowing of the artery from the heart to the lungs (pulmonary stenosis) and a hole between the two upper chambers of the heart (atrial septal defect). Other features of geleophysic dysplasia can include an enlarged liver (hepatomegaly) and recurrent respiratory and ear infections. In severe cases, a narrowing of the windpipe (tracheal stenosis) can cause serious breathing problems. As a result of heart and respiratory abnormalities, geleophysic dysplasia is often life-threatening in childhood. However, some affected people have lived into adulthood. Geleophysic dysplasia is a rare disorder whose prevalence is unknown. More than 30 affected individuals have been reported. Geleophysic dysplasia results from mutations in the ADAMTSL2 gene. This gene provides instructions for making a protein whose function is unclear. The protein is found in the extracellular matrix, which is the intricate lattice of proteins and other molecules that forms in the spaces between cells. Studies suggest that the ADAMTSL2 protein may play a role in the microfibrillar network, which is an organized clustering of thread-like filaments (called microfibrils) in the extracellular matrix. This network provides strength and flexibility to tissues throughout the body. Mutations in the ADAMTSL2 protein likely change the protein's 3-dimensional structure. Through a process that is poorly understood, ADAMTSL2 gene mutations alter the microfibrillar network in many different tissues. Impairment of this essential network disrupts the normal functions of cells, which likely contributes to the varied signs and symptoms of geleophysic dysplasia. Researchers are working to determine how mutations in the ADAMTSL2 gene lead to short stature, heart disease, and the other features of this condition. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) geleophysic dysplasia ? | Geleophysic dysplasia is an inherited condition that affects many parts of the body. It is characterized by abnormalities involving the bones, joints, heart, and skin. People with geleophysic dysplasia have short stature with very short hands and feet. Most also develop thickened skin and joint deformities called contractures, both of which significantly limit mobility. Affected individuals usually have a limited range of motion in their fingers, toes, wrists, and elbows. Additionally, contractures in the legs and hips cause many affected people to walk on their toes. The name of this condition, which comes from the Greek words for happy ("gelios") and nature ("physis"), is derived from the good-natured facial appearance seen in most affected individuals. The distinctive facial features associated with this condition include a round face with full cheeks, a small nose with upturned nostrils, a broad nasal bridge, a thin upper lip, upturned corners of the mouth, and a flat area between the upper lip and the nose (philtrum). Geleophysic dysplasia is also characterized by heart (cardiac) problems, particularly abnormalities of the cardiac valves. These valves normally control the flow of blood through the heart. In people with geleophysic dysplasia, the cardiac valves thicken, which impedes blood flow and increases blood pressure in the heart. Other heart problems have also been reported in people with geleophysic dysplasia; these include a narrowing of the artery from the heart to the lungs (pulmonary stenosis) and a hole between the two upper chambers of the heart (atrial septal defect). Other features of geleophysic dysplasia can include an enlarged liver (hepatomegaly) and recurrent respiratory and ear infections. In severe cases, a narrowing of the windpipe (tracheal stenosis) can cause serious breathing problems. As a result of heart and respiratory abnormalities, geleophysic dysplasia is often life-threatening in childhood. However, some affected people have lived into adulthood. |
Geleophysic dysplasia is an inherited condition that affects many parts of the body. It is characterized by abnormalities involving the bones, joints, heart, and skin. People with geleophysic dysplasia have short stature with very short hands and feet. Most also develop thickened skin and joint deformities called contractures, both of which significantly limit mobility. Affected individuals usually have a limited range of motion in their fingers, toes, wrists, and elbows. Additionally, contractures in the legs and hips cause many affected people to walk on their toes. The name of this condition, which comes from the Greek words for happy ("gelios") and nature ("physis"), is derived from the good-natured facial appearance seen in most affected individuals. The distinctive facial features associated with this condition include a round face with full cheeks, a small nose with upturned nostrils, a broad nasal bridge, a thin upper lip, upturned corners of the mouth, and a flat area between the upper lip and the nose (philtrum). Geleophysic dysplasia is also characterized by heart (cardiac) problems, particularly abnormalities of the cardiac valves. These valves normally control the flow of blood through the heart. In people with geleophysic dysplasia, the cardiac valves thicken, which impedes blood flow and increases blood pressure in the heart. Other heart problems have also been reported in people with geleophysic dysplasia; these include a narrowing of the artery from the heart to the lungs (pulmonary stenosis) and a hole between the two upper chambers of the heart (atrial septal defect). Other features of geleophysic dysplasia can include an enlarged liver (hepatomegaly) and recurrent respiratory and ear infections. In severe cases, a narrowing of the windpipe (tracheal stenosis) can cause serious breathing problems. As a result of heart and respiratory abnormalities, geleophysic dysplasia is often life-threatening in childhood. However, some affected people have lived into adulthood. Geleophysic dysplasia is a rare disorder whose prevalence is unknown. More than 30 affected individuals have been reported. Geleophysic dysplasia results from mutations in the ADAMTSL2 gene. This gene provides instructions for making a protein whose function is unclear. The protein is found in the extracellular matrix, which is the intricate lattice of proteins and other molecules that forms in the spaces between cells. Studies suggest that the ADAMTSL2 protein may play a role in the microfibrillar network, which is an organized clustering of thread-like filaments (called microfibrils) in the extracellular matrix. This network provides strength and flexibility to tissues throughout the body. Mutations in the ADAMTSL2 protein likely change the protein's 3-dimensional structure. Through a process that is poorly understood, ADAMTSL2 gene mutations alter the microfibrillar network in many different tissues. Impairment of this essential network disrupts the normal functions of cells, which likely contributes to the varied signs and symptoms of geleophysic dysplasia. Researchers are working to determine how mutations in the ADAMTSL2 gene lead to short stature, heart disease, and the other features of this condition. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by geleophysic dysplasia ? | Geleophysic dysplasia is a rare disorder whose prevalence is unknown. More than 30 affected individuals have been reported. |
Geleophysic dysplasia is an inherited condition that affects many parts of the body. It is characterized by abnormalities involving the bones, joints, heart, and skin. People with geleophysic dysplasia have short stature with very short hands and feet. Most also develop thickened skin and joint deformities called contractures, both of which significantly limit mobility. Affected individuals usually have a limited range of motion in their fingers, toes, wrists, and elbows. Additionally, contractures in the legs and hips cause many affected people to walk on their toes. The name of this condition, which comes from the Greek words for happy ("gelios") and nature ("physis"), is derived from the good-natured facial appearance seen in most affected individuals. The distinctive facial features associated with this condition include a round face with full cheeks, a small nose with upturned nostrils, a broad nasal bridge, a thin upper lip, upturned corners of the mouth, and a flat area between the upper lip and the nose (philtrum). Geleophysic dysplasia is also characterized by heart (cardiac) problems, particularly abnormalities of the cardiac valves. These valves normally control the flow of blood through the heart. In people with geleophysic dysplasia, the cardiac valves thicken, which impedes blood flow and increases blood pressure in the heart. Other heart problems have also been reported in people with geleophysic dysplasia; these include a narrowing of the artery from the heart to the lungs (pulmonary stenosis) and a hole between the two upper chambers of the heart (atrial septal defect). Other features of geleophysic dysplasia can include an enlarged liver (hepatomegaly) and recurrent respiratory and ear infections. In severe cases, a narrowing of the windpipe (tracheal stenosis) can cause serious breathing problems. As a result of heart and respiratory abnormalities, geleophysic dysplasia is often life-threatening in childhood. However, some affected people have lived into adulthood. Geleophysic dysplasia is a rare disorder whose prevalence is unknown. More than 30 affected individuals have been reported. Geleophysic dysplasia results from mutations in the ADAMTSL2 gene. This gene provides instructions for making a protein whose function is unclear. The protein is found in the extracellular matrix, which is the intricate lattice of proteins and other molecules that forms in the spaces between cells. Studies suggest that the ADAMTSL2 protein may play a role in the microfibrillar network, which is an organized clustering of thread-like filaments (called microfibrils) in the extracellular matrix. This network provides strength and flexibility to tissues throughout the body. Mutations in the ADAMTSL2 protein likely change the protein's 3-dimensional structure. Through a process that is poorly understood, ADAMTSL2 gene mutations alter the microfibrillar network in many different tissues. Impairment of this essential network disrupts the normal functions of cells, which likely contributes to the varied signs and symptoms of geleophysic dysplasia. Researchers are working to determine how mutations in the ADAMTSL2 gene lead to short stature, heart disease, and the other features of this condition. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to geleophysic dysplasia ? | Geleophysic dysplasia results from mutations in the ADAMTSL2 gene. This gene provides instructions for making a protein whose function is unclear. The protein is found in the extracellular matrix, which is the intricate lattice of proteins and other molecules that forms in the spaces between cells. Studies suggest that the ADAMTSL2 protein may play a role in the microfibrillar network, which is an organized clustering of thread-like filaments (called microfibrils) in the extracellular matrix. This network provides strength and flexibility to tissues throughout the body. Mutations in the ADAMTSL2 protein likely change the protein's 3-dimensional structure. Through a process that is poorly understood, ADAMTSL2 gene mutations alter the microfibrillar network in many different tissues. Impairment of this essential network disrupts the normal functions of cells, which likely contributes to the varied signs and symptoms of geleophysic dysplasia. Researchers are working to determine how mutations in the ADAMTSL2 gene lead to short stature, heart disease, and the other features of this condition. |
Geleophysic dysplasia is an inherited condition that affects many parts of the body. It is characterized by abnormalities involving the bones, joints, heart, and skin. People with geleophysic dysplasia have short stature with very short hands and feet. Most also develop thickened skin and joint deformities called contractures, both of which significantly limit mobility. Affected individuals usually have a limited range of motion in their fingers, toes, wrists, and elbows. Additionally, contractures in the legs and hips cause many affected people to walk on their toes. The name of this condition, which comes from the Greek words for happy ("gelios") and nature ("physis"), is derived from the good-natured facial appearance seen in most affected individuals. The distinctive facial features associated with this condition include a round face with full cheeks, a small nose with upturned nostrils, a broad nasal bridge, a thin upper lip, upturned corners of the mouth, and a flat area between the upper lip and the nose (philtrum). Geleophysic dysplasia is also characterized by heart (cardiac) problems, particularly abnormalities of the cardiac valves. These valves normally control the flow of blood through the heart. In people with geleophysic dysplasia, the cardiac valves thicken, which impedes blood flow and increases blood pressure in the heart. Other heart problems have also been reported in people with geleophysic dysplasia; these include a narrowing of the artery from the heart to the lungs (pulmonary stenosis) and a hole between the two upper chambers of the heart (atrial septal defect). Other features of geleophysic dysplasia can include an enlarged liver (hepatomegaly) and recurrent respiratory and ear infections. In severe cases, a narrowing of the windpipe (tracheal stenosis) can cause serious breathing problems. As a result of heart and respiratory abnormalities, geleophysic dysplasia is often life-threatening in childhood. However, some affected people have lived into adulthood. Geleophysic dysplasia is a rare disorder whose prevalence is unknown. More than 30 affected individuals have been reported. Geleophysic dysplasia results from mutations in the ADAMTSL2 gene. This gene provides instructions for making a protein whose function is unclear. The protein is found in the extracellular matrix, which is the intricate lattice of proteins and other molecules that forms in the spaces between cells. Studies suggest that the ADAMTSL2 protein may play a role in the microfibrillar network, which is an organized clustering of thread-like filaments (called microfibrils) in the extracellular matrix. This network provides strength and flexibility to tissues throughout the body. Mutations in the ADAMTSL2 protein likely change the protein's 3-dimensional structure. Through a process that is poorly understood, ADAMTSL2 gene mutations alter the microfibrillar network in many different tissues. Impairment of this essential network disrupts the normal functions of cells, which likely contributes to the varied signs and symptoms of geleophysic dysplasia. Researchers are working to determine how mutations in the ADAMTSL2 gene lead to short stature, heart disease, and the other features of this condition. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is geleophysic dysplasia inherited ? | This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. |
Geleophysic dysplasia is an inherited condition that affects many parts of the body. It is characterized by abnormalities involving the bones, joints, heart, and skin. People with geleophysic dysplasia have short stature with very short hands and feet. Most also develop thickened skin and joint deformities called contractures, both of which significantly limit mobility. Affected individuals usually have a limited range of motion in their fingers, toes, wrists, and elbows. Additionally, contractures in the legs and hips cause many affected people to walk on their toes. The name of this condition, which comes from the Greek words for happy ("gelios") and nature ("physis"), is derived from the good-natured facial appearance seen in most affected individuals. The distinctive facial features associated with this condition include a round face with full cheeks, a small nose with upturned nostrils, a broad nasal bridge, a thin upper lip, upturned corners of the mouth, and a flat area between the upper lip and the nose (philtrum). Geleophysic dysplasia is also characterized by heart (cardiac) problems, particularly abnormalities of the cardiac valves. These valves normally control the flow of blood through the heart. In people with geleophysic dysplasia, the cardiac valves thicken, which impedes blood flow and increases blood pressure in the heart. Other heart problems have also been reported in people with geleophysic dysplasia; these include a narrowing of the artery from the heart to the lungs (pulmonary stenosis) and a hole between the two upper chambers of the heart (atrial septal defect). Other features of geleophysic dysplasia can include an enlarged liver (hepatomegaly) and recurrent respiratory and ear infections. In severe cases, a narrowing of the windpipe (tracheal stenosis) can cause serious breathing problems. As a result of heart and respiratory abnormalities, geleophysic dysplasia is often life-threatening in childhood. However, some affected people have lived into adulthood. Geleophysic dysplasia is a rare disorder whose prevalence is unknown. More than 30 affected individuals have been reported. Geleophysic dysplasia results from mutations in the ADAMTSL2 gene. This gene provides instructions for making a protein whose function is unclear. The protein is found in the extracellular matrix, which is the intricate lattice of proteins and other molecules that forms in the spaces between cells. Studies suggest that the ADAMTSL2 protein may play a role in the microfibrillar network, which is an organized clustering of thread-like filaments (called microfibrils) in the extracellular matrix. This network provides strength and flexibility to tissues throughout the body. Mutations in the ADAMTSL2 protein likely change the protein's 3-dimensional structure. Through a process that is poorly understood, ADAMTSL2 gene mutations alter the microfibrillar network in many different tissues. Impairment of this essential network disrupts the normal functions of cells, which likely contributes to the varied signs and symptoms of geleophysic dysplasia. Researchers are working to determine how mutations in the ADAMTSL2 gene lead to short stature, heart disease, and the other features of this condition. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for geleophysic dysplasia ? | These resources address the diagnosis or management of geleophysic dysplasia: - Gene Review: Gene Review: Geleophysic Dysplasia - Genetic Testing Registry: Geleophysic dysplasia 2 - MedlinePlus Encyclopedia: Short Stature These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Hyperparathyroidism-jaw tumor syndrome is a condition characterized by overactivity of the parathyroid glands (hyperparathyroidism). The four parathyroid glands are located in the neck and secrete a hormone that regulates the body's use of calcium. Hyperparathyroidism disrupts the normal balance of calcium in the blood, which can lead to kidney stones, thinning of the bones (osteoporosis), nausea, vomiting, high blood pressure (hypertension), weakness, and fatigue. In people with hyperthyroidism-jaw tumor syndrome, hyperparathyroidism is caused by tumors that form in the parathyroid glands. Typically only one of the four parathyroid glands is affected, but in some people, tumors are found in more than one gland. The tumors are usually noncancerous (benign), in which case they are called adenomas. Approximately 15 percent of people with hyperparathyroidism-jaw tumor syndrome develop a cancerous tumor called parathyroid carcinoma. People with hyperparathyroidism-jaw tumor syndrome may also have a type of benign tumor called a fibroma in the jaw. Even though jaw tumors are specified in the name of this condition, it is estimated that only 25 to 50 percent of affected individuals have this symptom. Other tumors, both benign and cancerous, are often seen in hyperparathyroidism-jaw tumor syndrome. For example, tumors of the uterus occur in about 75 percent of women with this condition. The kidneys are affected in about 20 percent of people with hyperparathyroidism-jaw tumor syndrome. Benign kidney cysts are the most common kidney feature, but a rare tumor called Wilms tumor and other types of kidney tumor have also been found. The exact prevalence of hyperparathyroidism-jaw tumor syndrome is unknown. Approximately 200 cases have been reported in the medical literature. Mutations in the CDC73 gene (also known as the HRPT2 gene) cause hyperparathyroidism-jaw tumor syndrome. The CDC73 gene provides instructions for making a protein called parafibromin. This protein is found throughout the body and is likely involved in gene transcription, which is the first step in protein production. Parafibromin is also thought to play a role in cell growth and division (proliferation), either promoting or inhibiting cell proliferation depending on signals within the cell. CDC73 gene mutations cause hyperparathyroidism-jaw tumor syndrome by reducing the amount of functional parafibromin that is produced. Most of these mutations result in a parafibromin protein that is abnormally short and nonfunctional. Without functional parafibromin, cell proliferation is not properly regulated. Uncontrolled cell division can lead to the formation of tumors. It is unknown why only certain tissues seem to be affected by changes in parafibromin. Some people with hyperparathyroidism-jaw tumor syndrome do not have identified mutations in the CDC73 gene. The cause of the condition in these individuals is unknown. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) hyperparathyroidism-jaw tumor syndrome ? | Hyperparathyroidism-jaw tumor syndrome is a condition characterized by overactivity of the parathyroid glands (hyperparathyroidism). The four parathyroid glands are located in the neck and secrete a hormone that regulates the body's use of calcium. Hyperparathyroidism disrupts the normal balance of calcium in the blood, which can lead to kidney stones, thinning of the bones (osteoporosis), nausea, vomiting, high blood pressure (hypertension), weakness, and fatigue. In people with hyperthyroidism-jaw tumor syndrome, hyperparathyroidism is caused by tumors that form in the parathyroid glands. Typically only one of the four parathyroid glands is affected, but in some people, tumors are found in more than one gland. The tumors are usually noncancerous (benign), in which case they are called adenomas. Approximately 15 percent of people with hyperparathyroidism-jaw tumor syndrome develop a cancerous tumor called parathyroid carcinoma. People with hyperparathyroidism-jaw tumor syndrome may also have a type of benign tumor called a fibroma in the jaw. Even though jaw tumors are specified in the name of this condition, it is estimated that only 25 to 50 percent of affected individuals have this symptom. Other tumors, both benign and cancerous, are often seen in hyperparathyroidism-jaw tumor syndrome. For example, tumors of the uterus occur in about 75 percent of women with this condition. The kidneys are affected in about 20 percent of people with hyperparathyroidism-jaw tumor syndrome. Benign kidney cysts are the most common kidney feature, but a rare tumor called Wilms tumor and other types of kidney tumor have also been found. |
Hyperparathyroidism-jaw tumor syndrome is a condition characterized by overactivity of the parathyroid glands (hyperparathyroidism). The four parathyroid glands are located in the neck and secrete a hormone that regulates the body's use of calcium. Hyperparathyroidism disrupts the normal balance of calcium in the blood, which can lead to kidney stones, thinning of the bones (osteoporosis), nausea, vomiting, high blood pressure (hypertension), weakness, and fatigue. In people with hyperthyroidism-jaw tumor syndrome, hyperparathyroidism is caused by tumors that form in the parathyroid glands. Typically only one of the four parathyroid glands is affected, but in some people, tumors are found in more than one gland. The tumors are usually noncancerous (benign), in which case they are called adenomas. Approximately 15 percent of people with hyperparathyroidism-jaw tumor syndrome develop a cancerous tumor called parathyroid carcinoma. People with hyperparathyroidism-jaw tumor syndrome may also have a type of benign tumor called a fibroma in the jaw. Even though jaw tumors are specified in the name of this condition, it is estimated that only 25 to 50 percent of affected individuals have this symptom. Other tumors, both benign and cancerous, are often seen in hyperparathyroidism-jaw tumor syndrome. For example, tumors of the uterus occur in about 75 percent of women with this condition. The kidneys are affected in about 20 percent of people with hyperparathyroidism-jaw tumor syndrome. Benign kidney cysts are the most common kidney feature, but a rare tumor called Wilms tumor and other types of kidney tumor have also been found. The exact prevalence of hyperparathyroidism-jaw tumor syndrome is unknown. Approximately 200 cases have been reported in the medical literature. Mutations in the CDC73 gene (also known as the HRPT2 gene) cause hyperparathyroidism-jaw tumor syndrome. The CDC73 gene provides instructions for making a protein called parafibromin. This protein is found throughout the body and is likely involved in gene transcription, which is the first step in protein production. Parafibromin is also thought to play a role in cell growth and division (proliferation), either promoting or inhibiting cell proliferation depending on signals within the cell. CDC73 gene mutations cause hyperparathyroidism-jaw tumor syndrome by reducing the amount of functional parafibromin that is produced. Most of these mutations result in a parafibromin protein that is abnormally short and nonfunctional. Without functional parafibromin, cell proliferation is not properly regulated. Uncontrolled cell division can lead to the formation of tumors. It is unknown why only certain tissues seem to be affected by changes in parafibromin. Some people with hyperparathyroidism-jaw tumor syndrome do not have identified mutations in the CDC73 gene. The cause of the condition in these individuals is unknown. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by hyperparathyroidism-jaw tumor syndrome ? | The exact prevalence of hyperparathyroidism-jaw tumor syndrome is unknown. Approximately 200 cases have been reported in the medical literature. |
Hyperparathyroidism-jaw tumor syndrome is a condition characterized by overactivity of the parathyroid glands (hyperparathyroidism). The four parathyroid glands are located in the neck and secrete a hormone that regulates the body's use of calcium. Hyperparathyroidism disrupts the normal balance of calcium in the blood, which can lead to kidney stones, thinning of the bones (osteoporosis), nausea, vomiting, high blood pressure (hypertension), weakness, and fatigue. In people with hyperthyroidism-jaw tumor syndrome, hyperparathyroidism is caused by tumors that form in the parathyroid glands. Typically only one of the four parathyroid glands is affected, but in some people, tumors are found in more than one gland. The tumors are usually noncancerous (benign), in which case they are called adenomas. Approximately 15 percent of people with hyperparathyroidism-jaw tumor syndrome develop a cancerous tumor called parathyroid carcinoma. People with hyperparathyroidism-jaw tumor syndrome may also have a type of benign tumor called a fibroma in the jaw. Even though jaw tumors are specified in the name of this condition, it is estimated that only 25 to 50 percent of affected individuals have this symptom. Other tumors, both benign and cancerous, are often seen in hyperparathyroidism-jaw tumor syndrome. For example, tumors of the uterus occur in about 75 percent of women with this condition. The kidneys are affected in about 20 percent of people with hyperparathyroidism-jaw tumor syndrome. Benign kidney cysts are the most common kidney feature, but a rare tumor called Wilms tumor and other types of kidney tumor have also been found. The exact prevalence of hyperparathyroidism-jaw tumor syndrome is unknown. Approximately 200 cases have been reported in the medical literature. Mutations in the CDC73 gene (also known as the HRPT2 gene) cause hyperparathyroidism-jaw tumor syndrome. The CDC73 gene provides instructions for making a protein called parafibromin. This protein is found throughout the body and is likely involved in gene transcription, which is the first step in protein production. Parafibromin is also thought to play a role in cell growth and division (proliferation), either promoting or inhibiting cell proliferation depending on signals within the cell. CDC73 gene mutations cause hyperparathyroidism-jaw tumor syndrome by reducing the amount of functional parafibromin that is produced. Most of these mutations result in a parafibromin protein that is abnormally short and nonfunctional. Without functional parafibromin, cell proliferation is not properly regulated. Uncontrolled cell division can lead to the formation of tumors. It is unknown why only certain tissues seem to be affected by changes in parafibromin. Some people with hyperparathyroidism-jaw tumor syndrome do not have identified mutations in the CDC73 gene. The cause of the condition in these individuals is unknown. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to hyperparathyroidism-jaw tumor syndrome ? | Mutations in the CDC73 gene (also known as the HRPT2 gene) cause hyperparathyroidism-jaw tumor syndrome. The CDC73 gene provides instructions for making a protein called parafibromin. This protein is found throughout the body and is likely involved in gene transcription, which is the first step in protein production. Parafibromin is also thought to play a role in cell growth and division (proliferation), either promoting or inhibiting cell proliferation depending on signals within the cell. CDC73 gene mutations cause hyperparathyroidism-jaw tumor syndrome by reducing the amount of functional parafibromin that is produced. Most of these mutations result in a parafibromin protein that is abnormally short and nonfunctional. Without functional parafibromin, cell proliferation is not properly regulated. Uncontrolled cell division can lead to the formation of tumors. It is unknown why only certain tissues seem to be affected by changes in parafibromin. Some people with hyperparathyroidism-jaw tumor syndrome do not have identified mutations in the CDC73 gene. The cause of the condition in these individuals is unknown. |
Hyperparathyroidism-jaw tumor syndrome is a condition characterized by overactivity of the parathyroid glands (hyperparathyroidism). The four parathyroid glands are located in the neck and secrete a hormone that regulates the body's use of calcium. Hyperparathyroidism disrupts the normal balance of calcium in the blood, which can lead to kidney stones, thinning of the bones (osteoporosis), nausea, vomiting, high blood pressure (hypertension), weakness, and fatigue. In people with hyperthyroidism-jaw tumor syndrome, hyperparathyroidism is caused by tumors that form in the parathyroid glands. Typically only one of the four parathyroid glands is affected, but in some people, tumors are found in more than one gland. The tumors are usually noncancerous (benign), in which case they are called adenomas. Approximately 15 percent of people with hyperparathyroidism-jaw tumor syndrome develop a cancerous tumor called parathyroid carcinoma. People with hyperparathyroidism-jaw tumor syndrome may also have a type of benign tumor called a fibroma in the jaw. Even though jaw tumors are specified in the name of this condition, it is estimated that only 25 to 50 percent of affected individuals have this symptom. Other tumors, both benign and cancerous, are often seen in hyperparathyroidism-jaw tumor syndrome. For example, tumors of the uterus occur in about 75 percent of women with this condition. The kidneys are affected in about 20 percent of people with hyperparathyroidism-jaw tumor syndrome. Benign kidney cysts are the most common kidney feature, but a rare tumor called Wilms tumor and other types of kidney tumor have also been found. The exact prevalence of hyperparathyroidism-jaw tumor syndrome is unknown. Approximately 200 cases have been reported in the medical literature. Mutations in the CDC73 gene (also known as the HRPT2 gene) cause hyperparathyroidism-jaw tumor syndrome. The CDC73 gene provides instructions for making a protein called parafibromin. This protein is found throughout the body and is likely involved in gene transcription, which is the first step in protein production. Parafibromin is also thought to play a role in cell growth and division (proliferation), either promoting or inhibiting cell proliferation depending on signals within the cell. CDC73 gene mutations cause hyperparathyroidism-jaw tumor syndrome by reducing the amount of functional parafibromin that is produced. Most of these mutations result in a parafibromin protein that is abnormally short and nonfunctional. Without functional parafibromin, cell proliferation is not properly regulated. Uncontrolled cell division can lead to the formation of tumors. It is unknown why only certain tissues seem to be affected by changes in parafibromin. Some people with hyperparathyroidism-jaw tumor syndrome do not have identified mutations in the CDC73 gene. The cause of the condition in these individuals is unknown. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is hyperparathyroidism-jaw tumor syndrome inherited ? | This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. |
Hyperparathyroidism-jaw tumor syndrome is a condition characterized by overactivity of the parathyroid glands (hyperparathyroidism). The four parathyroid glands are located in the neck and secrete a hormone that regulates the body's use of calcium. Hyperparathyroidism disrupts the normal balance of calcium in the blood, which can lead to kidney stones, thinning of the bones (osteoporosis), nausea, vomiting, high blood pressure (hypertension), weakness, and fatigue. In people with hyperthyroidism-jaw tumor syndrome, hyperparathyroidism is caused by tumors that form in the parathyroid glands. Typically only one of the four parathyroid glands is affected, but in some people, tumors are found in more than one gland. The tumors are usually noncancerous (benign), in which case they are called adenomas. Approximately 15 percent of people with hyperparathyroidism-jaw tumor syndrome develop a cancerous tumor called parathyroid carcinoma. People with hyperparathyroidism-jaw tumor syndrome may also have a type of benign tumor called a fibroma in the jaw. Even though jaw tumors are specified in the name of this condition, it is estimated that only 25 to 50 percent of affected individuals have this symptom. Other tumors, both benign and cancerous, are often seen in hyperparathyroidism-jaw tumor syndrome. For example, tumors of the uterus occur in about 75 percent of women with this condition. The kidneys are affected in about 20 percent of people with hyperparathyroidism-jaw tumor syndrome. Benign kidney cysts are the most common kidney feature, but a rare tumor called Wilms tumor and other types of kidney tumor have also been found. The exact prevalence of hyperparathyroidism-jaw tumor syndrome is unknown. Approximately 200 cases have been reported in the medical literature. Mutations in the CDC73 gene (also known as the HRPT2 gene) cause hyperparathyroidism-jaw tumor syndrome. The CDC73 gene provides instructions for making a protein called parafibromin. This protein is found throughout the body and is likely involved in gene transcription, which is the first step in protein production. Parafibromin is also thought to play a role in cell growth and division (proliferation), either promoting or inhibiting cell proliferation depending on signals within the cell. CDC73 gene mutations cause hyperparathyroidism-jaw tumor syndrome by reducing the amount of functional parafibromin that is produced. Most of these mutations result in a parafibromin protein that is abnormally short and nonfunctional. Without functional parafibromin, cell proliferation is not properly regulated. Uncontrolled cell division can lead to the formation of tumors. It is unknown why only certain tissues seem to be affected by changes in parafibromin. Some people with hyperparathyroidism-jaw tumor syndrome do not have identified mutations in the CDC73 gene. The cause of the condition in these individuals is unknown. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for hyperparathyroidism-jaw tumor syndrome ? | These resources address the diagnosis or management of hyperparathyroidism-jaw tumor syndrome: - Gene Review: Gene Review: CDC73-Related Disorders - Genetic Testing Registry: Hyperparathyroidism 2 - MedlinePlus Encyclopedia: Hyperparathyroidism These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Waardenburg syndrome is a group of genetic conditions that can cause hearing loss and changes in coloring (pigmentation) of the hair, skin, and eyes. Although most people with Waardenburg syndrome have normal hearing, moderate to profound hearing loss can occur in one or both ears. The hearing loss is present from birth (congenital). People with this condition often have very pale blue eyes or different colored eyes, such as one blue eye and one brown eye. Sometimes one eye has segments of two different colors. Distinctive hair coloring (such as a patch of white hair or hair that prematurely turns gray) is another common sign of the condition. The features of Waardenburg syndrome vary among affected individuals, even among people in the same family. There are four recognized types of Waardenburg syndrome, which are distinguished by their physical characteristics and sometimes by their genetic cause. Types I and II have very similar features, although people with type I almost always have eyes that appear widely spaced and people with type II do not. In addition, hearing loss occurs more often in people with type II than in those with type I. Type III (sometimes called Klein-Waardenburg syndrome) includes abnormalities of the arms and hands in addition to hearing loss and changes in pigmentation. Type IV (also known as Waardenburg-Hirschsprung disease or Waardenburg-Shah syndrome) has signs and symptoms of both Waardenburg syndrome and Hirschsprung disease, an intestinal disorder that causes severe constipation or blockage of the intestine. Waardenburg syndrome affects an estimated 1 in 40,000 people. It accounts for 2 to 5 percent of all cases of congenital hearing loss. Types I and II are the most common forms of Waardenburg syndrome, while types III and IV are rare. Variants (also known as mutations) in the EDN3, EDNRB, MITF, PAX3, SNAI2, and SOX10 genes can cause Waardenburg syndrome. These genes are involved in the formation and development of several types of cells, including pigment-producing cells called melanocytes. Melanocytes make a pigment called melanin, which contributes to skin, hair, and eye color and plays an essential role in the normal function of the inner ear. Variants in any of these genes disrupt the normal development of melanocytes, leading to abnormal pigmentation of the skin, hair, and eyes and problems with hearing. Waardenburg syndrome types I and III are caused by variants in the PAX3 gene. Variants in the MITF or SNAI2 gene can cause Waardenburg syndrome type II. Variants in the SOX10, EDN3, or EDNRB gene can cause Waardenburg syndrome type IV. In addition to melanocyte development, these genes are important for the development of nerve cells in the large intestine. Variants in any of these genes result in hearing loss, changes in pigmentation, and intestinal problems related to Hirschsprung disease. In some cases, the genetic cause of Waardenburg syndrome has not been identified. Waardenburg syndrome is usually inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. A small percentage of cases result from new variants in the gene; these cases occur in people with no history of the disorder in their family. Some cases of Waardenburg syndrome type II and type IV appear to have an autosomal recessive pattern of inheritance, which means both copies of the gene in each cell have variants. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the altered gene, but do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) Waardenburg syndrome ? | Waardenburg syndrome is a group of genetic conditions that can cause hearing loss and changes in coloring (pigmentation) of the hair, skin, and eyes. Although most people with Waardenburg syndrome have normal hearing, moderate to profound hearing loss can occur in one or both ears. The hearing loss is present from birth (congenital). People with this condition often have very pale blue eyes or different colored eyes, such as one blue eye and one brown eye. Sometimes one eye has segments of two different colors. Distinctive hair coloring (such as a patch of white hair or hair that prematurely turns gray) is another common sign of the condition. The features of Waardenburg syndrome vary among affected individuals, even among people in the same family. The four known types of Waardenburg syndrome are distinguished by their physical characteristics and sometimes by their genetic cause. Types I and II have very similar features, although people with type I almost always have eyes that appear widely spaced and people with type II do not. In addition, hearing loss occurs more often in people with type II than in those with type I. Type III (sometimes called Klein-Waardenburg syndrome) includes abnormalities of the upper limbs in addition to hearing loss and changes in pigmentation. Type IV (also known as Waardenburg-Shah syndrome) has signs and symptoms of both Waardenburg syndrome and Hirschsprung disease, an intestinal disorder that causes severe constipation or blockage of the intestine. |
Waardenburg syndrome is a group of genetic conditions that can cause hearing loss and changes in coloring (pigmentation) of the hair, skin, and eyes. Although most people with Waardenburg syndrome have normal hearing, moderate to profound hearing loss can occur in one or both ears. The hearing loss is present from birth (congenital). People with this condition often have very pale blue eyes or different colored eyes, such as one blue eye and one brown eye. Sometimes one eye has segments of two different colors. Distinctive hair coloring (such as a patch of white hair or hair that prematurely turns gray) is another common sign of the condition. The features of Waardenburg syndrome vary among affected individuals, even among people in the same family. There are four recognized types of Waardenburg syndrome, which are distinguished by their physical characteristics and sometimes by their genetic cause. Types I and II have very similar features, although people with type I almost always have eyes that appear widely spaced and people with type II do not. In addition, hearing loss occurs more often in people with type II than in those with type I. Type III (sometimes called Klein-Waardenburg syndrome) includes abnormalities of the arms and hands in addition to hearing loss and changes in pigmentation. Type IV (also known as Waardenburg-Hirschsprung disease or Waardenburg-Shah syndrome) has signs and symptoms of both Waardenburg syndrome and Hirschsprung disease, an intestinal disorder that causes severe constipation or blockage of the intestine. Waardenburg syndrome affects an estimated 1 in 40,000 people. It accounts for 2 to 5 percent of all cases of congenital hearing loss. Types I and II are the most common forms of Waardenburg syndrome, while types III and IV are rare. Variants (also known as mutations) in the EDN3, EDNRB, MITF, PAX3, SNAI2, and SOX10 genes can cause Waardenburg syndrome. These genes are involved in the formation and development of several types of cells, including pigment-producing cells called melanocytes. Melanocytes make a pigment called melanin, which contributes to skin, hair, and eye color and plays an essential role in the normal function of the inner ear. Variants in any of these genes disrupt the normal development of melanocytes, leading to abnormal pigmentation of the skin, hair, and eyes and problems with hearing. Waardenburg syndrome types I and III are caused by variants in the PAX3 gene. Variants in the MITF or SNAI2 gene can cause Waardenburg syndrome type II. Variants in the SOX10, EDN3, or EDNRB gene can cause Waardenburg syndrome type IV. In addition to melanocyte development, these genes are important for the development of nerve cells in the large intestine. Variants in any of these genes result in hearing loss, changes in pigmentation, and intestinal problems related to Hirschsprung disease. In some cases, the genetic cause of Waardenburg syndrome has not been identified. Waardenburg syndrome is usually inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. A small percentage of cases result from new variants in the gene; these cases occur in people with no history of the disorder in their family. Some cases of Waardenburg syndrome type II and type IV appear to have an autosomal recessive pattern of inheritance, which means both copies of the gene in each cell have variants. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the altered gene, but do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by Waardenburg syndrome ? | Waardenburg syndrome affects an estimated 1 in 40,000 people. It accounts for 2 to 5 percent of all cases of congenital hearing loss. Types I and II are the most common forms of Waardenburg syndrome, while types III and IV are rare. |
Waardenburg syndrome is a group of genetic conditions that can cause hearing loss and changes in coloring (pigmentation) of the hair, skin, and eyes. Although most people with Waardenburg syndrome have normal hearing, moderate to profound hearing loss can occur in one or both ears. The hearing loss is present from birth (congenital). People with this condition often have very pale blue eyes or different colored eyes, such as one blue eye and one brown eye. Sometimes one eye has segments of two different colors. Distinctive hair coloring (such as a patch of white hair or hair that prematurely turns gray) is another common sign of the condition. The features of Waardenburg syndrome vary among affected individuals, even among people in the same family. There are four recognized types of Waardenburg syndrome, which are distinguished by their physical characteristics and sometimes by their genetic cause. Types I and II have very similar features, although people with type I almost always have eyes that appear widely spaced and people with type II do not. In addition, hearing loss occurs more often in people with type II than in those with type I. Type III (sometimes called Klein-Waardenburg syndrome) includes abnormalities of the arms and hands in addition to hearing loss and changes in pigmentation. Type IV (also known as Waardenburg-Hirschsprung disease or Waardenburg-Shah syndrome) has signs and symptoms of both Waardenburg syndrome and Hirschsprung disease, an intestinal disorder that causes severe constipation or blockage of the intestine. Waardenburg syndrome affects an estimated 1 in 40,000 people. It accounts for 2 to 5 percent of all cases of congenital hearing loss. Types I and II are the most common forms of Waardenburg syndrome, while types III and IV are rare. Variants (also known as mutations) in the EDN3, EDNRB, MITF, PAX3, SNAI2, and SOX10 genes can cause Waardenburg syndrome. These genes are involved in the formation and development of several types of cells, including pigment-producing cells called melanocytes. Melanocytes make a pigment called melanin, which contributes to skin, hair, and eye color and plays an essential role in the normal function of the inner ear. Variants in any of these genes disrupt the normal development of melanocytes, leading to abnormal pigmentation of the skin, hair, and eyes and problems with hearing. Waardenburg syndrome types I and III are caused by variants in the PAX3 gene. Variants in the MITF or SNAI2 gene can cause Waardenburg syndrome type II. Variants in the SOX10, EDN3, or EDNRB gene can cause Waardenburg syndrome type IV. In addition to melanocyte development, these genes are important for the development of nerve cells in the large intestine. Variants in any of these genes result in hearing loss, changes in pigmentation, and intestinal problems related to Hirschsprung disease. In some cases, the genetic cause of Waardenburg syndrome has not been identified. Waardenburg syndrome is usually inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. A small percentage of cases result from new variants in the gene; these cases occur in people with no history of the disorder in their family. Some cases of Waardenburg syndrome type II and type IV appear to have an autosomal recessive pattern of inheritance, which means both copies of the gene in each cell have variants. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the altered gene, but do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the genetic changes related to Waardenburg syndrome ? | Mutations in the EDN3, EDNRB, MITF, PAX3, SNAI2, and SOX10 genes can cause Waardenburg syndrome. These genes are involved in the formation and development of several types of cells, including pigment-producing cells called melanocytes. Melanocytes make a pigment called melanin, which contributes to skin, hair, and eye color and plays an essential role in the normal function of the inner ear. Mutations in any of these genes disrupt the normal development of melanocytes, leading to abnormal pigmentation of the skin, hair, and eyes and problems with hearing. Types I and III Waardenburg syndrome are caused by mutations in the PAX3 gene. Mutations in the MITF and SNAI2 genes are responsible for type II Waardenburg syndrome. Mutations in the SOX10, EDN3, or EDNRB genes cause type IV Waardenburg syndrome. In addition to melanocyte development, these genes are important for the development of nerve cells in the large intestine. Mutations in any of these genes result in hearing loss, changes in pigmentation, and intestinal problems related to Hirschsprung disease. |
Waardenburg syndrome is a group of genetic conditions that can cause hearing loss and changes in coloring (pigmentation) of the hair, skin, and eyes. Although most people with Waardenburg syndrome have normal hearing, moderate to profound hearing loss can occur in one or both ears. The hearing loss is present from birth (congenital). People with this condition often have very pale blue eyes or different colored eyes, such as one blue eye and one brown eye. Sometimes one eye has segments of two different colors. Distinctive hair coloring (such as a patch of white hair or hair that prematurely turns gray) is another common sign of the condition. The features of Waardenburg syndrome vary among affected individuals, even among people in the same family. There are four recognized types of Waardenburg syndrome, which are distinguished by their physical characteristics and sometimes by their genetic cause. Types I and II have very similar features, although people with type I almost always have eyes that appear widely spaced and people with type II do not. In addition, hearing loss occurs more often in people with type II than in those with type I. Type III (sometimes called Klein-Waardenburg syndrome) includes abnormalities of the arms and hands in addition to hearing loss and changes in pigmentation. Type IV (also known as Waardenburg-Hirschsprung disease or Waardenburg-Shah syndrome) has signs and symptoms of both Waardenburg syndrome and Hirschsprung disease, an intestinal disorder that causes severe constipation or blockage of the intestine. Waardenburg syndrome affects an estimated 1 in 40,000 people. It accounts for 2 to 5 percent of all cases of congenital hearing loss. Types I and II are the most common forms of Waardenburg syndrome, while types III and IV are rare. Variants (also known as mutations) in the EDN3, EDNRB, MITF, PAX3, SNAI2, and SOX10 genes can cause Waardenburg syndrome. These genes are involved in the formation and development of several types of cells, including pigment-producing cells called melanocytes. Melanocytes make a pigment called melanin, which contributes to skin, hair, and eye color and plays an essential role in the normal function of the inner ear. Variants in any of these genes disrupt the normal development of melanocytes, leading to abnormal pigmentation of the skin, hair, and eyes and problems with hearing. Waardenburg syndrome types I and III are caused by variants in the PAX3 gene. Variants in the MITF or SNAI2 gene can cause Waardenburg syndrome type II. Variants in the SOX10, EDN3, or EDNRB gene can cause Waardenburg syndrome type IV. In addition to melanocyte development, these genes are important for the development of nerve cells in the large intestine. Variants in any of these genes result in hearing loss, changes in pigmentation, and intestinal problems related to Hirschsprung disease. In some cases, the genetic cause of Waardenburg syndrome has not been identified. Waardenburg syndrome is usually inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. A small percentage of cases result from new variants in the gene; these cases occur in people with no history of the disorder in their family. Some cases of Waardenburg syndrome type II and type IV appear to have an autosomal recessive pattern of inheritance, which means both copies of the gene in each cell have variants. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the altered gene, but do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | Is Waardenburg syndrome inherited ? | Waardenburg syndrome is usually inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. A small percentage of cases result from new mutations in the gene; these cases occur in people with no history of the disorder in their family. Some cases of type II and type IV Waardenburg syndrome appear to have an autosomal recessive pattern of inheritance, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition. |
Waardenburg syndrome is a group of genetic conditions that can cause hearing loss and changes in coloring (pigmentation) of the hair, skin, and eyes. Although most people with Waardenburg syndrome have normal hearing, moderate to profound hearing loss can occur in one or both ears. The hearing loss is present from birth (congenital). People with this condition often have very pale blue eyes or different colored eyes, such as one blue eye and one brown eye. Sometimes one eye has segments of two different colors. Distinctive hair coloring (such as a patch of white hair or hair that prematurely turns gray) is another common sign of the condition. The features of Waardenburg syndrome vary among affected individuals, even among people in the same family. There are four recognized types of Waardenburg syndrome, which are distinguished by their physical characteristics and sometimes by their genetic cause. Types I and II have very similar features, although people with type I almost always have eyes that appear widely spaced and people with type II do not. In addition, hearing loss occurs more often in people with type II than in those with type I. Type III (sometimes called Klein-Waardenburg syndrome) includes abnormalities of the arms and hands in addition to hearing loss and changes in pigmentation. Type IV (also known as Waardenburg-Hirschsprung disease or Waardenburg-Shah syndrome) has signs and symptoms of both Waardenburg syndrome and Hirschsprung disease, an intestinal disorder that causes severe constipation or blockage of the intestine. Waardenburg syndrome affects an estimated 1 in 40,000 people. It accounts for 2 to 5 percent of all cases of congenital hearing loss. Types I and II are the most common forms of Waardenburg syndrome, while types III and IV are rare. Variants (also known as mutations) in the EDN3, EDNRB, MITF, PAX3, SNAI2, and SOX10 genes can cause Waardenburg syndrome. These genes are involved in the formation and development of several types of cells, including pigment-producing cells called melanocytes. Melanocytes make a pigment called melanin, which contributes to skin, hair, and eye color and plays an essential role in the normal function of the inner ear. Variants in any of these genes disrupt the normal development of melanocytes, leading to abnormal pigmentation of the skin, hair, and eyes and problems with hearing. Waardenburg syndrome types I and III are caused by variants in the PAX3 gene. Variants in the MITF or SNAI2 gene can cause Waardenburg syndrome type II. Variants in the SOX10, EDN3, or EDNRB gene can cause Waardenburg syndrome type IV. In addition to melanocyte development, these genes are important for the development of nerve cells in the large intestine. Variants in any of these genes result in hearing loss, changes in pigmentation, and intestinal problems related to Hirschsprung disease. In some cases, the genetic cause of Waardenburg syndrome has not been identified. Waardenburg syndrome is usually inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. A small percentage of cases result from new variants in the gene; these cases occur in people with no history of the disorder in their family. Some cases of Waardenburg syndrome type II and type IV appear to have an autosomal recessive pattern of inheritance, which means both copies of the gene in each cell have variants. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the altered gene, but do not show signs and symptoms of the condition. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What are the treatments for Waardenburg syndrome ? | These resources address the diagnosis or management of Waardenburg syndrome: - Gene Review: Gene Review: Waardenburg Syndrome Type I - Genetic Testing Registry: Klein-Waardenberg's syndrome - Genetic Testing Registry: Waardenburg syndrome type 1 - Genetic Testing Registry: Waardenburg syndrome type 2A - Genetic Testing Registry: Waardenburg syndrome type 2B - Genetic Testing Registry: Waardenburg syndrome type 2C - Genetic Testing Registry: Waardenburg syndrome type 2D - Genetic Testing Registry: Waardenburg syndrome type 4A - MedlinePlus Encyclopedia: Waardenburg Syndrome These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care |
Hajdu-Cheney syndrome is a rare disorder that can affect many parts of the body, particularly the bones. Loss of bone tissue from the hands and feet (acro-osteolysis) is a characteristic feature of the condition. The fingers and toes are short and broad, and they may become shorter over time as bone at the tips continues to break down. Bone loss in the fingers can interfere with fine motor skills, such as picking up small objects. Bone abnormalities throughout the body are common in Hajdu-Cheney syndrome. Affected individuals develop osteoporosis, which causes the bones to be brittle and prone to fracture. Many affected individuals experience breakage (compression fractures) of the spinal bones (vertebrae). Some also develop abnormal curvature of the spine (scoliosis or kyphosis). Hajdu-Cheney syndrome also affects the shape and strength of the long bones in the arms and legs. The abnormalities associated with this condition lead to short stature. Hajdu-Cheney syndrome also causes abnormalities of the skull bones, including the bones of the face. The shape of the skull is often described as dolichocephalic, which means it is elongated from back to front. In many affected individuals, the bone at the back of the skull bulges outward, causing a bump called a prominent occiput. Distinctive facial features associated with this condition include widely spaced and downward-slanting eyes, eyebrows that grow together in the middle (synophrys), low-set ears, a sunken appearance of the middle of the face (midface hypoplasia), and a large space between the nose and upper lip (a long philtrum). Some affected children are born with an opening in the roof of the mouth called a cleft palate or with a high arched palate. In affected adults, the facial features are often described as "coarse." Other features of Hajdu-Cheney syndrome found in some affected individuals include joint abnormalities, particularly an unusually large range of joint movement (hypermobility); dental problems; hearing loss; a deep, gravelly voice; excess body hair; recurrent infections in childhood; heart defects; and kidney abnormalities such as the growth of multiple fluid-filled cysts (polycystic kidneys). Some people with this condition have delayed development in childhood, but the delays are usually mild. The most serious complications of Hajdu-Cheney syndrome, which occur in about half of all affected individuals, are abnormalities known as platybasia and basilar invagination. Platybasia is a flattening of the base of the skull caused by thinning and softening of the skull bones. Basilar invagination occurs when the softened bones allow part of the spine to protrude abnormally through the opening at the bottom of the skull, pushing into the lower parts of the brain. These abnormalities can lead to severe neurological problems, including headaches, abnormal vision and balance, a buildup of fluid in the brain (hydrocephalus), abnormal breathing, and sudden death. The signs and symptoms of Hajdu-Cheney syndrome vary greatly among affected individuals, even among members of the same family. Many of the disorder's features, such as acro-osteolysis and some of the characteristic facial features, are not present at birth but become apparent in childhood or later. The risk of developing platybasia and basilar invagination also increases over time. The features of Hajdu-Cheney syndrome overlap significantly with those of a condition called serpentine fibula-polycystic kidney syndrome (SFPKS). Although they used to be considered separate disorders, researchers discovered that the two conditions are associated with mutations in the same gene. Based on these similarities, many researchers now consider Hajdu-Cheney syndrome and SFPKS to be variants of the same condition. Hajdu-Cheney syndrome is a rare disease; its prevalence is unknown. Fewer than 100 affected individuals have been described in the medical literature. Hajdu-Cheney syndrome is associated with mutations in the NOTCH2 gene. This gene provides instructions for making a receptor called Notch2. Receptor proteins have specific sites into which certain other proteins, called ligands, fit like keys into locks. When a ligand binds to the Notch2 receptor, it triggers signals that are important for the normal development and function of many different types of cells. Studies suggest that signaling through the Notch2 receptor is important for the early development of bones and later for bone remodeling, a normal process in which old bone is removed and new bone is created to replace it. Notch2 signaling also appears to be involved in the development of the heart, kidneys, teeth, and other parts of the body. Mutations in a specific area near the end of the NOTCH2 gene are associated with Hajdu-Cheney syndrome. These mutations lead to a version of the Notch2 receptor that cannot be broken down normally. As a result, the receptor continues to be active even after signaling should stop. Researchers are unsure how excessive Notch2 signaling is related to the varied features of Hajdu-Cheney syndrome. They suspect that the skeletal features of the disorder, including acro-osteolysis, osteoporosis, and distinctive facial features, likely result from abnormal bone development and remodeling. Excess signaling through the overactive Notch2 receptor may increase the removal of old bone, reduce the formation of new bone, or both. It is less clear how the overactive receptor contributes to the other signs and symptoms of this condition. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered NOTCH2 gene in each cell is sufficient to cause the disorder. Most cases result from new mutations in the gene and occur in people with no history of the disorder in their family. Less commonly, an affected person inherits the mutation from one affected parent. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | What is (are) Hajdu-Cheney syndrome ? | Hajdu-Cheney syndrome is a rare disorder that can affect many parts of the body, particularly the bones. Loss of bone tissue from the hands and feet (acro-osteolysis) is a characteristic feature of the condition. The fingers and toes are short and broad, and they may become shorter over time as bone at the tips continues to break down. Bone loss in the fingers can interfere with fine motor skills, such as picking up small objects. Bone abnormalities throughout the body are common in Hajdu-Cheney syndrome. Affected individuals develop osteoporosis, which causes the bones to be brittle and prone to fracture. Many affected individuals experience breakage (compression fractures) of the spinal bones (vertebrae). Some also develop abnormal curvature of the spine (scoliosis or kyphosis). Hajdu-Cheney syndrome also affects the shape and strength of the long bones in the arms and legs. The abnormalities associated with this condition lead to short stature. Hajdu-Cheney syndrome also causes abnormalities of the skull bones, including the bones of the face. The shape of the skull is often described as dolichocephalic, which means it is elongated from back to front. In many affected individuals, the bone at the back of the skull bulges outward, causing a bump called a prominent occiput. Distinctive facial features associated with this condition include widely spaced and downward-slanting eyes, eyebrows that grow together in the middle (synophrys), low-set ears, a sunken appearance of the middle of the face (midface hypoplasia), and a large space between the nose and upper lip (a long philtrum). Some affected children are born with an opening in the roof of the mouth called a cleft palate or with a high arched palate. In affected adults, the facial features are often described as "coarse." Other features of Hajdu-Cheney syndrome found in some affected individuals include joint abnormalities, particularly an unusually large range of joint movement (hypermobility); dental problems; hearing loss; a deep, gravelly voice; excess body hair; recurrent infections in childhood; heart defects; and kidney abnormalities such as the growth of multiple fluid-filled cysts (polycystic kidneys). Some people with this condition have delayed development in childhood, but the delays are usually mild. The most serious complications of Hajdu-Cheney syndrome, which occur in about half of all affected individuals, are abnormalities known as platybasia and basilar invagination. Platybasia is a flattening of the base of the skull caused by thinning and softening of the skull bones. Basilar invagination occurs when the softened bones allow part of the spine to protrude abnormally through the opening at the bottom of the skull, pushing into the lower parts of the brain. These abnormalities can lead to severe neurological problems, including headaches, abnormal vision and balance, a buildup of fluid in the brain (hydrocephalus), abnormal breathing, and sudden death. The signs and symptoms of Hajdu-Cheney syndrome vary greatly among affected individuals, even among members of the same family. Many of the disorder's features, such as acro-osteolysis and some of the characteristic facial features, are not present at birth but become apparent in childhood or later. The risk of developing platybasia and basilar invagination also increases over time. The features of Hajdu-Cheney syndrome overlap significantly with those of a condition called serpentine fibula-polycystic kidney syndrome (SFPKS). Although they used to be considered separate disorders, researchers discovered that the two conditions are associated with mutations in the same gene. Based on these similarities, many researchers now consider Hajdu-Cheney syndrome and SFPKS to be variants of the same condition. |
Hajdu-Cheney syndrome is a rare disorder that can affect many parts of the body, particularly the bones. Loss of bone tissue from the hands and feet (acro-osteolysis) is a characteristic feature of the condition. The fingers and toes are short and broad, and they may become shorter over time as bone at the tips continues to break down. Bone loss in the fingers can interfere with fine motor skills, such as picking up small objects. Bone abnormalities throughout the body are common in Hajdu-Cheney syndrome. Affected individuals develop osteoporosis, which causes the bones to be brittle and prone to fracture. Many affected individuals experience breakage (compression fractures) of the spinal bones (vertebrae). Some also develop abnormal curvature of the spine (scoliosis or kyphosis). Hajdu-Cheney syndrome also affects the shape and strength of the long bones in the arms and legs. The abnormalities associated with this condition lead to short stature. Hajdu-Cheney syndrome also causes abnormalities of the skull bones, including the bones of the face. The shape of the skull is often described as dolichocephalic, which means it is elongated from back to front. In many affected individuals, the bone at the back of the skull bulges outward, causing a bump called a prominent occiput. Distinctive facial features associated with this condition include widely spaced and downward-slanting eyes, eyebrows that grow together in the middle (synophrys), low-set ears, a sunken appearance of the middle of the face (midface hypoplasia), and a large space between the nose and upper lip (a long philtrum). Some affected children are born with an opening in the roof of the mouth called a cleft palate or with a high arched palate. In affected adults, the facial features are often described as "coarse." Other features of Hajdu-Cheney syndrome found in some affected individuals include joint abnormalities, particularly an unusually large range of joint movement (hypermobility); dental problems; hearing loss; a deep, gravelly voice; excess body hair; recurrent infections in childhood; heart defects; and kidney abnormalities such as the growth of multiple fluid-filled cysts (polycystic kidneys). Some people with this condition have delayed development in childhood, but the delays are usually mild. The most serious complications of Hajdu-Cheney syndrome, which occur in about half of all affected individuals, are abnormalities known as platybasia and basilar invagination. Platybasia is a flattening of the base of the skull caused by thinning and softening of the skull bones. Basilar invagination occurs when the softened bones allow part of the spine to protrude abnormally through the opening at the bottom of the skull, pushing into the lower parts of the brain. These abnormalities can lead to severe neurological problems, including headaches, abnormal vision and balance, a buildup of fluid in the brain (hydrocephalus), abnormal breathing, and sudden death. The signs and symptoms of Hajdu-Cheney syndrome vary greatly among affected individuals, even among members of the same family. Many of the disorder's features, such as acro-osteolysis and some of the characteristic facial features, are not present at birth but become apparent in childhood or later. The risk of developing platybasia and basilar invagination also increases over time. The features of Hajdu-Cheney syndrome overlap significantly with those of a condition called serpentine fibula-polycystic kidney syndrome (SFPKS). Although they used to be considered separate disorders, researchers discovered that the two conditions are associated with mutations in the same gene. Based on these similarities, many researchers now consider Hajdu-Cheney syndrome and SFPKS to be variants of the same condition. Hajdu-Cheney syndrome is a rare disease; its prevalence is unknown. Fewer than 100 affected individuals have been described in the medical literature. Hajdu-Cheney syndrome is associated with mutations in the NOTCH2 gene. This gene provides instructions for making a receptor called Notch2. Receptor proteins have specific sites into which certain other proteins, called ligands, fit like keys into locks. When a ligand binds to the Notch2 receptor, it triggers signals that are important for the normal development and function of many different types of cells. Studies suggest that signaling through the Notch2 receptor is important for the early development of bones and later for bone remodeling, a normal process in which old bone is removed and new bone is created to replace it. Notch2 signaling also appears to be involved in the development of the heart, kidneys, teeth, and other parts of the body. Mutations in a specific area near the end of the NOTCH2 gene are associated with Hajdu-Cheney syndrome. These mutations lead to a version of the Notch2 receptor that cannot be broken down normally. As a result, the receptor continues to be active even after signaling should stop. Researchers are unsure how excessive Notch2 signaling is related to the varied features of Hajdu-Cheney syndrome. They suspect that the skeletal features of the disorder, including acro-osteolysis, osteoporosis, and distinctive facial features, likely result from abnormal bone development and remodeling. Excess signaling through the overactive Notch2 receptor may increase the removal of old bone, reduce the formation of new bone, or both. It is less clear how the overactive receptor contributes to the other signs and symptoms of this condition. This condition is inherited in an autosomal dominant pattern, which means one copy of the altered NOTCH2 gene in each cell is sufficient to cause the disorder. Most cases result from new mutations in the gene and occur in people with no history of the disorder in their family. Less commonly, an affected person inherits the mutation from one affected parent. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health. | How many people are affected by Hajdu-Cheney syndrome ? | Hajdu-Cheney syndrome is a rare disease; its prevalence is unknown. Fewer than 100 affected individuals have been described in the medical literature. |
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