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What are the genetic changes related to Roberts syndrome ?
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Mutations in the ESCO2 gene cause Roberts syndrome. This gene provides instructions for making a protein that is important for proper chromosome separation during cell division. Before cells divide, they must copy all of their chromosomes. The copied DNA from each chromosome is arranged into two identical structures, called sister chromatids. The ESCO2 protein plays an important role in establishing the glue that holds the sister chromatids together until the chromosomes are ready to separate. All identified mutations in the ESCO2 gene prevent the cell from producing any functional ESCO2 protein, which causes some of the glue between sister chromatids to be missing around the chromosome's constriction point (centromere). In Roberts syndrome, cells respond to abnormal sister chromatid attachment by delaying cell division. Delayed cell division can be a signal that the cell should undergo self-destruction. The signs and symptoms of Roberts syndrome may result from the loss of cells from various tissues during early development. Because both mildly and severely affected individuals lack any functional ESCO2 protein, the underlying cause of the variation in disease severity remains unknown. Researchers suspect that other genetic and environmental factors may be involved.
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Is Roberts syndrome inherited ?
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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.
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What are the treatments for Roberts syndrome ?
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These resources address the diagnosis or management of Roberts syndrome: - Gene Review: Gene Review: Roberts Syndrome - Genetic Testing Registry: Roberts-SC phocomelia syndrome - MedlinePlus Encyclopedia: Contracture deformity - MedlinePlus Encyclopedia: Microcephaly 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
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What is (are) Cant syndrome ?
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Cant syndrome is a rare condition characterized by excess hair growth (hypertrichosis), a distinctive facial appearance, heart defects, and several other abnormalities. The features of the disorder vary among affected individuals. People with Cant syndrome have thick scalp hair that extends onto the forehead and grows down onto the cheeks in front of the ears. They also have increased body hair, especially on the back, arms, and legs. Most affected individuals have a large head (macrocephaly) and distinctive facial features that are described as "coarse." These include a broad nasal bridge, skin folds covering the inner corner of the eyes (epicanthal folds), and a wide mouth with full lips. As affected individuals get older, the face lengthens, the chin becomes more prominent, and the eyes become deep-set. Many infants with Cant syndrome are born with a heart defect such as an enlarged heart (cardiomegaly) or patent ductus arteriosus (PDA). The ductus arteriosus is a connection between two major arteries, the aorta and the pulmonary artery. This connection is open during fetal development and normally closes shortly after birth. However, the ductus arteriosus remains open, or patent, in babies with PDA. Other heart problems have also been found in people with Cant syndrome, including an abnormal buildup of fluid around the heart (pericardial effusion) and high blood pressure in the blood vessels that carry blood from the heart to the lungs (pulmonary hypertension). Additional features of this condition include distinctive skeletal abnormalities, a large body size (macrosomia) at birth, a reduced amount of fat under the skin (subcutaneous fat) beginning in childhood, deep horizontal creases in the palms of the hands and soles of the feet, and an increased susceptibility to respiratory infections. Other signs and symptoms that have been reported include abnormal swelling in the body's tissues (lymphedema), side-to-side curvature of the spine (scoliosis), and reduced bone density (osteopenia). Some affected children have weak muscle tone (hypotonia) that delays the development of motor skills such as sitting, standing, and walking. Most have mildly delayed speech, and some affected children have mild intellectual disability or learning problems.
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How many people are affected by Cant syndrome ?
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Cant syndrome is a rare condition. About three dozen affected individuals have been reported in the medical literature.
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What are the genetic changes related to Cant syndrome ?
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Cant syndrome results from mutations in the ABCC9 gene. This gene provides instructions for making one part (subunit) of a channel that transports charged potassium atoms (potassium ions) across cell membranes. Mutations in the ABCC9 gene alter the structure of the potassium channel, which causes the channel to open when it should be closed. It is unknown how this problem with potassium channel function leads to excess hair growth, heart defects, and the other features of Cant syndrome.
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Is Cant syndrome inherited ?
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This condition is inherited in an autosomal dominant pattern, which means one copy of the altered ABCC9 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. In a few reported cases, an affected person has inherited the mutation from one affected parent.
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What are the treatments for Cant syndrome ?
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These resources address the diagnosis or management of Cant syndrome: - Gene Review: Gene Review: Cant syndrome - Genetic Testing Registry: Hypertrichotic osteochondrodysplasia 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
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What is (are) Griscelli syndrome ?
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Griscelli syndrome is an inherited condition characterized by unusually light (hypopigmented) skin and light silvery-gray hair starting in infancy. Researchers have identified three types of this disorder, which are distinguished by their genetic cause and pattern of signs and symptoms. Griscelli syndrome type 1 involves severe problems with brain function in addition to the distinctive skin and hair coloring. Affected individuals typically have delayed development, intellectual disability, seizures, weak muscle tone (hypotonia), and eye and vision abnormalities. Another condition called Elejalde disease has many of the same signs and symptoms, and some researchers have proposed that Griscelli syndrome type 1 and Elejalde disease are actually the same disorder. People with Griscelli syndrome type 2 have immune system abnormalities in addition to having hypopigmented skin and hair. Affected individuals are prone to recurrent infections. They also develop an immune condition called hemophagocytic lymphohistiocytosis (HLH), in which the immune system produces too many activated immune cells called T-lymphocytes and macrophages (histiocytes). Overactivity of these cells can damage organs and tissues throughout the body, causing life-threatening complications if the condition is untreated. People with Griscelli syndrome type 2 do not have the neurological abnormalities of type 1. Unusually light skin and hair coloring are the only features of Griscelli syndrome type 3. People with this form of the disorder do not have neurological abnormalities or immune system problems.
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How many people are affected by Griscelli syndrome ?
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Griscelli syndrome is a rare condition; its prevalence is unknown. Type 2 appears to be the most common of the three known types.
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What are the genetic changes related to Griscelli syndrome ?
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The three types of Griscelli syndrome are caused by mutations in different genes: Type 1 results from mutations in the MYO5A gene, type 2 is caused by mutations in the RAB27A gene, and type 3 results from mutations in the MLPH gene. The proteins produced from these genes are found in pigment-producing cells called melanocytes. Within these cells, the proteins work together to transport structures called melanosomes. These structures produce a pigment called melanin, which is the substance that gives skin, hair, and eyes their color (pigmentation). Melanosomes are formed near the center of melanocytes, but they must be transported to the outer edge of these cells and then transferred into other types of cells to provide normal pigmentation. Mutations in any of the three genes, MYO5A, RAB27A, or MLPH, impair the normal transport of melanosomes within melanocytes. As a result, these structures clump near the center of melanocytes, trapping melanin within these cells and preventing normal pigmentation of skin and hair. The clumps of pigment, which can be seen in hair shafts when viewed under a microscope, are a hallmark feature of the condition. In addition to their roles in melanosome transport, the MYO5A and RAB27A genes have functions elsewhere in the body. Specifically, the protein produced from the MYO5A gene transports materials within nerve cells (neurons) that appear to be critical for cell function. The protein produced from the RAB27A gene is found in immune system cells, where it is involved in the release of certain compounds that kill foreign invaders (such as viruses and bacteria). Mutations in these genes impair these critical cell activities, leading to the neurological problems and immune system abnormalities found in Griscelli syndrome types 1 and 2, respectively.
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Is Griscelli syndrome inherited ?
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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.
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What are the treatments for Griscelli syndrome ?
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These resources address the diagnosis or management of Griscelli syndrome: - Genetic Testing Registry: Griscelli syndrome type 1 - Genetic Testing Registry: Griscelli syndrome type 2 - Genetic Testing Registry: Griscelli syndrome type 3 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
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What is (are) Horner syndrome ?
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Horner syndrome is a disorder that affects the eye and surrounding tissues on one side of the face and results from paralysis of certain nerves. Horner syndrome can appear at any time of life; in about 5 percent of affected individuals, the disorder is present from birth (congenital). Horner syndrome is characterized by drooping of the upper eyelid (ptosis) on the affected side, a constricted pupil in the affected eye (miosis) resulting in unequal pupil size (anisocoria), and absent sweating (anhidrosis) on the affected side of the face. Sinking of the eye into its cavity (enophthalmos) and a bloodshot eye often occur in this disorder. In people with Horner syndrome that occurs before the age of 2, the colored part (iris) of the eyes may differ in color (iris heterochromia), with the iris of the affected eye being lighter in color than that of the unaffected eye. Individuals who develop Horner syndrome after age 2 do not generally have iris heterochromia. The abnormalities in the eye area related to Horner syndrome do not generally affect vision or health. However, the nerve damage that causes Horner syndrome may result from other health problems, some of which can be life-threatening.
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How many people are affected by Horner syndrome ?
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About 1 in 6,250 babies are born with Horner syndrome. The incidence of Horner syndrome that appears later is unknown, but it is considered an uncommon disorder.
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What are the genetic changes related to Horner syndrome ?
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Although congenital Horner syndrome can be passed down in families, no associated genes have been identified. Horner syndrome that appears after the newborn period (acquired Horner syndrome) and most cases of congenital Horner syndrome result from damage to nerves called the cervical sympathetics. These nerves belong to the part of the nervous system that controls involuntary functions (the autonomic nervous system). Within the autonomic nervous system, the nerves are part of a subdivision called the sympathetic nervous system. The cervical sympathetic nerves control several functions in the eye and face such as dilation of the pupil and sweating. Problems with the function of these nerves cause the signs and symptoms of Horner syndrome. Horner syndrome that occurs very early in life can lead to iris heterochromia because the development of the pigmentation (coloring) of the iris is under the control of the cervical sympathetic nerves. Damage to the cervical sympathetic nerves can be caused by a direct injury to the nerves themselves, which can result from trauma that might occur during a difficult birth, surgery, or accidental injury. The nerves related to Horner syndrome can also be damaged by a benign or cancerous tumor, for example a childhood cancer of the nerve tissues called a neuroblastoma. Horner syndrome can also be caused by problems with the artery that supplies blood to the head and neck (the carotid artery) on the affected side, resulting in loss of blood flow to the nerves. Some individuals with congenital Horner syndrome have a lack of development (agenesis) of the carotid artery. Tearing of the layers of the carotid artery wall (carotid artery dissection) can also lead to Horner syndrome. The signs and symptoms of Horner syndrome can also occur during a migraine headache. When the headache is gone, the signs and symptoms of Horner syndrome usually also go away. Some people with Horner syndrome have neither a known problem that would lead to nerve damage nor any history of the disorder in their family. These cases are referred to as idiopathic Horner syndrome.
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Is Horner syndrome inherited ?
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Horner syndrome is usually not inherited and occurs in individuals with no history of the disorder in their family. Acquired Horner syndrome and most cases of congenital Horner syndrome have nongenetic causes. Rarely, congenital Horner syndrome is passed down within a family in a pattern that appears to be autosomal dominant, which means one copy of an altered gene in each cell is sufficient to cause the disorder. However, no genes associated with Horner syndrome have been identified.
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What are the treatments for Horner syndrome ?
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These resources address the diagnosis or management of Horner syndrome: - Genetic Testing Registry: Horner syndrome, congenital 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
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What is (are) adult-onset leukoencephalopathy with axonal spheroids and pigmented glia ?
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Adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP) is a neurological condition characterized by changes to certain areas of the brain. A hallmark of ALSP is leukoencephalopathy, which is the alteration of a type of brain tissue called white matter. White matter consists of nerve fibers (axons) covered by a substance called myelin that insulates and protects them. The axons extend from nerve cells (neurons) and transmit nerve impulses throughout the body. Areas of damage to this brain tissue (white matter lesions) can be seen with magnetic resonance imaging (MRI). Another feature of ALSP is swellings called spheroids in the axons of the brain, which are a sign of axon damage. Also common in ALSP are abnormally pigmented glial cells. Glial cells are specialized brain cells that protect and maintain neurons. Damage to myelin and neurons is thought to contribute to many of the neurological signs and symptoms in people with ALSP. Symptoms of ALSP usually begin in a person's forties and worsen over time. Personality changes, including depression and a loss of social inhibitions, are among the earliest symptoms of ALSP. Affected individuals may develop memory loss and loss of executive function, which is the ability to plan and implement actions and develop problem-solving strategies. Loss of this function impairs skills such as impulse control, self-monitoring, and focusing attention appropriately. Some people with ALSP have mild seizures, usually only when the condition begins. As ALSP progresses, it causes a severe decline in thinking and reasoning abilities (dementia). Over time, motor skills are affected, and people with ALSP may have difficulty walking. Many develop a pattern of movement abnormalities known as parkinsonism, which includes unusually slow movement (bradykinesia), involuntary trembling (tremor), and muscle stiffness (rigidity). The pattern of cognitive and motor problems are variable, even among individuals in the same family, although almost all affected individuals ultimately become unable to walk, speak, and care for themselves. ALSP was previously thought to be two separate conditions, hereditary diffuse leukoencephalopathy with spheroids (HDLS) and familial pigmentary orthochromatic leukodystrophy (POLD), both of which cause very similar white matter damage and cognitive and movement problems. POLD was thought to be distinguished by the presence of pigmented glial cells and an absence of spheroids; however, people with HDLS can have pigmented cells, too, and people with POLD can have spheroids. HDLS and POLD are now considered to be part of the same disease spectrum, which researchers have recommended calling ALSP.
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How many people are affected by adult-onset leukoencephalopathy with axonal spheroids and pigmented glia ?
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ALSP is thought to be a rare disorder, although the prevalence is unknown. Because it can be mistaken for other disorders with similar symptoms, ALSP may be underdiagnosed.
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What are the genetic changes related to adult-onset leukoencephalopathy with axonal spheroids and pigmented glia ?
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ALSP is caused by mutations in the CSF1R gene. This gene provides instructions for making a protein called colony stimulating factor 1 receptor (CSF-1 receptor), which is found in the outer membrane of certain types of cells, including glial cells. The CSF-1 receptor triggers signaling pathways that control many important cellular processes, such as cell growth and division (proliferation) and maturation of the cell to take on specific functions (differentiation). CSF1R gene mutations in ALSP lead to an altered CSF-1 receptor protein that is likely unable to stimulate cell signaling pathways. However, it is unclear how the gene mutations lead to white matter damage or cognitive and movement problems in people with ALSP.
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Is adult-onset leukoencephalopathy with axonal spheroids and pigmented glia inherited ?
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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 inherits the mutation from one affected parent. Other cases result from new mutations in the gene and occur in people with no history of the disorder in their family.
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What are the treatments for adult-onset leukoencephalopathy with axonal spheroids and pigmented glia ?
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These resources address the diagnosis or management of ALSP: - Gene Review: Gene Review: Adult-Onset Leukoencephalopathy with Axonal Spheroids and Pigmented Glia - Genetic Testing Registry: Hereditary diffuse leukoencephalopathy with spheroids - MedlinePlus Encyclopedia: Dementia 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
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What is (are) cutis laxa ?
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Cutis laxa is a disorder of connective tissue, which is the tissue that forms the body's supportive framework. Connective tissue provides structure and strength to the muscles, joints, organs, and skin. The term "cutis laxa" is Latin for loose or lax skin, and this condition is characterized by skin that is sagging and not stretchy (inelastic). The skin often hangs in loose folds, causing the face and other parts of the body to have a droopy appearance. Extremely wrinkled skin may be particularly noticeable on the neck and in the armpits and groin. Cutis laxa can also affect connective tissue in other parts of the body, including the heart, blood vessels, joints, intestines, and lungs. The disorder can cause heart problems and abnormal narrowing, bulging, or tearing of critical arteries. Affected individuals may have soft out-pouchings in the lower abdomen (inguinal hernia) or around the belly button (umbilical hernia). Pouches called diverticula can also develop in the walls of certain organs, such as the bladder and intestines. During childhood, some people with cutis laxa develop a lung disease called emphysema, which can make it difficult to breathe. Depending on which organs and tissues are affected, the signs and symptoms of cutis laxa can range from mild to life-threatening. Researchers have described several different forms of cutis laxa. The forms are often distinguished by their pattern of inheritance: autosomal dominant, autosomal recessive, or X-linked. In general, the autosomal recessive forms of cutis laxa tend to be more severe than the autosomal dominant form. In addition to the features described above, some people with autosomal recessive cutis laxa have delayed development, intellectual disability, seizures, and problems with movement that can worsen over time. The X-linked form of cutis laxa is often called occipital horn syndrome. This form of the disorder is considered a mild type of Menkes syndrome, which is a condition that affects copper levels in the body. In addition to sagging and inelastic skin, occipital horn syndrome is characterized by wedge-shaped calcium deposits in a bone at the base of the skull (the occipital bone), coarse hair, and loose joints.
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How many people are affected by cutis laxa ?
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Cutis laxa is a rare disorder. About 200 affected families worldwide have been reported.
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What are the genetic changes related to cutis laxa ?
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Cutis laxa can be caused by mutations in the ATP6V0A2, ATP7A, EFEMP2, ELN, or FBLN5 gene. Most of these genes are involved in the formation and function of elastic fibers, which are slender bundles of proteins that provide strength and flexibility to connective tissue throughout the body. Elastic fibers allow the skin to stretch, the lungs to expand and contract, and arteries to handle blood flowing through them at high pressure. The major component of elastic fibers, a protein called elastin, is produced from the ELN gene. Other proteins that appear to have critical roles in the assembly of elastic fibers are produced from the EFEMP2, FBLN5, and ATP6V0A2 genes. Mutations in any of these genes disrupt the formation, assembly, or function of elastic fibers. A shortage of these fibers weakens connective tissue in the skin, arteries, lungs, and other organs. These defects in connective tissue underlie the major features of cutis laxa. Occipital horn syndrome is caused by mutations in the ATP7A gene. This gene provides instructions for making a protein that is important for regulating copper levels in the body. Mutations in the ATP7A gene result in poor distribution of copper to the body's cells. A reduced supply of copper can decrease the activity of numerous copper-containing enzymes that are necessary for the structure and function of bone, skin, hair, blood vessels, and the nervous system. The signs and symptoms of occipital horn syndrome are caused by the reduced activity of these copper-containing enzymes. Mutations in the genes described above account for only a small percentage of all cases of cutis laxa. Researchers suspect that mutations in other genes, which have not been identified, can also be responsible for the condition. Rare cases of cutis laxa are acquired, which means they are probably not caused by inherited gene mutations. Acquired cutis laxa appears later in life and is related to the destruction of normal elastic fibers. The causes of acquired cutis laxa are unclear, although it may occur as a side effect of treatment with medications that remove copper from the body (copper chelating drugs).
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Is cutis laxa inherited ?
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Cutis laxa can have an autosomal dominant, autosomal recessive, or X-linked recessive pattern of inheritance. When cutis laxa is caused by ELN mutations, it has an autosomal dominant inheritance pattern. Autosomal dominant inheritance means one copy of the altered gene in each cell is sufficient to cause the disorder. Rarely, cases of cutis laxa resulting from FBLN5 mutations can also have an autosomal dominant pattern of inheritance. Researchers have described at least two forms of autosomal recessive cutis laxa. Type I results from mutations in the EFEMP2 or FBLN5 gene, while type II is caused by mutations in the ATP6V02 gene. Autosomal recessive inheritance 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. Occipital horn syndrome has an X-linked recessive pattern of inheritance. It results from mutations in the ATP7A gene, which is located on the X chromosome. The X chromosome is one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation would have to occur in both copies of the gene to cause the disorder. Because it is unlikely that females will have two altered copies of this gene, males are affected by X-linked recessive disorders much more frequently than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.
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What are the treatments for cutis laxa ?
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These resources address the diagnosis or management of cutis laxa: - Gene Review: Gene Review: ATP6V0A2-Related Cutis Laxa - Gene Review: Gene Review: ATP7A-Related Copper Transport Disorders - Gene Review: Gene Review: EFEMP2-Related Cutis Laxa - Gene Review: Gene Review: FBLN5-Related Cutis Laxa - Genetic Testing Registry: Autosomal recessive cutis laxa type IA - Genetic Testing Registry: Cutis laxa with osteodystrophy - Genetic Testing Registry: Cutis laxa, X-linked - Genetic Testing Registry: Cutis laxa, autosomal dominant - MedlinePlus Encyclopedia: Colon Diverticula (image) - MedlinePlus Encyclopedia: Emphysema (image) - MedlinePlus Encyclopedia: Hernia 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
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What is (are) supravalvular aortic stenosis ?
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Supravalvular aortic stenosis (SVAS) is a heart defect that develops before birth. This defect is a narrowing (stenosis) of the large blood vessel that carries blood from the heart to the rest of the body (the aorta). The condition is described as supravalvular because the section of the aorta that is narrowed is located just above the valve that connects the aorta with the heart (the aortic valve). Some people with SVAS also have defects in other blood vessels, most commonly stenosis of the artery from the heart to the lungs (the pulmonary artery). An abnormal heart sound during a heartbeat (heart murmur) can often be heard during a chest exam. If SVAS is not treated, the aortic narrowing can lead to shortness of breath, chest pain, and ultimately heart failure. The severity of SVAS varies considerably, even among family members. Some affected individuals die in infancy, while others never experience symptoms of the disorder.
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How many people are affected by supravalvular aortic stenosis ?
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SVAS occurs in 1 in 20,000 newborns worldwide.
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What are the genetic changes related to supravalvular aortic stenosis ?
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Mutations in the ELN gene cause SVAS. The ELN gene provides instructions for making a protein called tropoelastin. Multiple copies of the tropoelastin protein attach to one another and are processed to form a mature protein called elastin. Elastin is the major component of elastic fibers, which are slender bundles of proteins that provide strength and flexibility to connective tissue (tissue that supports the body's joints and organs). Elastic fibers are found in the intricate lattice that forms in the spaces between cells (the extracellular matrix), where they give structural support to organs and tissues such as the heart, skin, lungs, ligaments, and blood vessels. Elastic fibers make up approximately 50 percent of the aorta, the rest being primarily muscle cells called vascular smooth muscle cells that line the aorta. Together, elastic fibers and vascular smooth muscle cells provide flexibility and resilience to the aorta. Most of the ELN gene mutations that cause SVAS lead to a decrease in the production of tropoelastin. A shortage of tropoelastin reduces the amount of mature elastin protein that is processed and available for forming elastic fibers. As a result, elastic fibers that make up the aorta are thinner than normal. To compensate, the smooth muscle cells that line the aorta increase in number, making the aorta thicker and narrower than usual. A thickened aorta is less flexible and resilient to the stress of constant blood flow and pumping of the heart. Over time, the wall of the aorta can become damaged. Aortic narrowing causes the heart to work harder to pump blood through the aorta, resulting in the signs and symptoms of SVAS.
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Is supravalvular aortic stenosis inherited ?
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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. However, some people who inherit the altered gene never develop features of SVAS. (This situation is known as reduced penetrance.) In some cases, a person inherits the mutation from one parent who has the mutation. Other cases result from new mutations in the gene and occur in people with no history of the disorder in their family.
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What are the treatments for supravalvular aortic stenosis ?
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These resources address the diagnosis or management of supravalvular aortic stenosis: - Children's Hospital of Philadelphia - Genetic Testing Registry: Supravalvar aortic stenosis - Monroe Carell Jr. Children's Hospital at Vanderbilt 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
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What is (are) hypohidrotic ectodermal dysplasia ?
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Hypohidrotic ectodermal dysplasia is one of about 150 types of ectodermal dysplasia in humans. Before birth, these disorders result in the abnormal development of structures including the skin, hair, nails, teeth, and sweat glands. Most people with hypohidrotic ectodermal dysplasia have a reduced ability to sweat (hypohidrosis) because they have fewer sweat glands than normal or their sweat glands do not function properly. Sweating is a major way that the body controls its temperature; as sweat evaporates from the skin, it cools the body. An inability to sweat can lead to a dangerously high body temperature (hyperthermia), particularly in hot weather. In some cases, hyperthermia can cause life-threatening medical problems. Affected individuals tend to have sparse scalp and body hair (hypotrichosis). The hair is often light-colored, brittle, and slow-growing. This condition is also characterized by absent teeth (hypodontia) or teeth that are malformed. The teeth that are present are frequently small and pointed. Hypohidrotic ectodermal dysplasia is associated with distinctive facial features including a prominent forehead, thick lips, and a flattened bridge of the nose. Additional features of this condition include thin, wrinkled, and dark-colored skin around the eyes; chronic skin problems such as eczema; and a bad-smelling discharge from the nose (ozena).
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How many people are affected by hypohidrotic ectodermal dysplasia ?
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Hypohidrotic ectodermal dysplasia is the most common form of ectodermal dysplasia in humans. It is estimated to affect at least 1 in 17,000 people worldwide.
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What are the genetic changes related to hypohidrotic ectodermal dysplasia ?
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Mutations in the EDA, EDAR, and EDARADD genes cause hypohidrotic ectodermal dysplasia. The EDA, EDAR, and EDARADD genes provide instructions for making proteins that work together during embryonic development. These proteins form part of a signaling pathway that is critical for the interaction between two cell layers, the ectoderm and the mesoderm. In the early embryo, these cell layers form the basis for many of the body's organs and tissues. Ectoderm-mesoderm interactions are essential for the formation of several structures that arise from the ectoderm, including the skin, hair, nails, teeth, and sweat glands. Mutations in the EDA, EDAR, or EDARADD gene prevent normal interactions between the ectoderm and the mesoderm and impair the normal development of hair, sweat glands, and teeth. The improper formation of these ectodermal structures leads to the characteristic features of hypohidrotic ectodermal dysplasia.
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Is hypohidrotic ectodermal dysplasia inherited ?
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Hypohidrotic ectodermal dysplasia has several different inheritance patterns. Most cases are caused by mutations in the EDA gene, which are inherited in an X-linked recessive pattern. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation must be present in both copies of the gene to cause the disorder. Males are affected by X-linked recessive disorders much more frequently than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons. In X-linked recessive inheritance, a female with one altered copy of the gene in each cell is called a carrier. In about 70 percent of cases, carriers of hypohidrotic ectodermal dysplasia experience some features of the condition. These signs and symptoms are usually mild and include a few missing or abnormal teeth, sparse hair, and some problems with sweat gland function. Some carriers, however, have more severe features of this disorder. Less commonly, hypohidrotic ectodermal dysplasia results from mutations in the EDAR or EDARADD gene. EDAR mutations can have an autosomal dominant or autosomal recessive pattern of inheritance, and EDARADD mutations have an autosomal recessive pattern of inheritance. Autosomal dominant inheritance means one copy of the altered gene in each cell is sufficient to cause the disorder. Autosomal recessive inheritance means two copies of the gene in each cell are altered. Most often, the parents of an individual with an autosomal recessive disorder are carriers of one copy of the altered gene but do not show signs and symptoms of the disorder.
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What are the treatments for hypohidrotic ectodermal dysplasia ?
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These resources address the diagnosis or management of hypohidrotic ectodermal dysplasia: - Gene Review: Gene Review: Hypohidrotic Ectodermal Dysplasia - Genetic Testing Registry: Autosomal dominant hypohidrotic ectodermal dysplasia - Genetic Testing Registry: Autosomal recessive hypohidrotic ectodermal dysplasia syndrome - Genetic Testing Registry: Hypohidrotic X-linked ectodermal dysplasia - MedlinePlus Encyclopedia: Ectodermal dysplasia - MedlinePlus Encyclopedia: Ozena - MedlinePlus Encyclopedia: Sweating - absent 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
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What is (are) Wolff-Parkinson-White syndrome ?
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Wolff-Parkinson-White syndrome is a condition characterized by abnormal electrical pathways in the heart that cause a disruption of the heart's normal rhythm (arrhythmia). The heartbeat is controlled by electrical signals that move through the heart in a highly coordinated way. A specialized cluster of cells called the atrioventricular node conducts electrical impulses from the heart's upper chambers (the atria) to the lower chambers (the ventricles). Impulses move through the atrioventricular node during each heartbeat, stimulating the ventricles to contract slightly later than the atria. People with Wolff-Parkinson-White syndrome are born with an extra connection in the heart, called an accessory pathway, that allows electrical signals to bypass the atrioventricular node and move from the atria to the ventricles faster than usual. The accessory pathway may also transmit electrical impulses abnormally from the ventricles back to the atria. This extra connection can disrupt the coordinated movement of electrical signals through the heart, leading to an abnormally fast heartbeat (tachycardia) and other arrhythmias. Resulting symptoms include dizziness, a sensation of fluttering or pounding in the chest (palpitations), shortness of breath, and fainting (syncope). In rare cases, arrhythmias associated with Wolff-Parkinson-White syndrome can lead to cardiac arrest and sudden death. The most common arrhythmia associated with Wolff-Parkinson-White syndrome is called paroxysmal supraventricular tachycardia. Complications of Wolff-Parkinson-White syndrome can occur at any age, although some individuals born with an accessory pathway in the heart never experience any health problems associated with the condition. Wolff-Parkinson-White syndrome often occurs with other structural abnormalities of the heart or underlying heart disease. The most common heart defect associated with the condition is Ebstein anomaly, which affects the valve that allows blood to flow from the right atrium to the right ventricle (the tricuspid valve). Additionally, Wolff-Parkinson-White syndrome can be a component of several other genetic syndromes, including hypokalemic periodic paralysis (a condition that causes episodes of extreme muscle weakness), Pompe disease (a disorder characterized by the storage of excess glycogen), and tuberous sclerosis (a condition that results in the growth of noncancerous tumors in many parts of the body).
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How many people are affected by Wolff-Parkinson-White syndrome ?
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Wolff-Parkinson-White syndrome affects 1 to 3 in 1,000 people worldwide. Only a small fraction of these cases appear to run in families. Wolff-Parkinson-White syndrome is a common cause of an arrhythmia known as paroxysmal supraventricular tachycardia. Wolff-Parkinson-White syndrome is the most frequent cause of this abnormal heart rhythm in the Chinese population, where it is responsible for more than 70 percent of cases.
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What are the genetic changes related to Wolff-Parkinson-White syndrome ?
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Mutations in the PRKAG2 gene cause Wolff-Parkinson-White syndrome. A small percentage of all cases of Wolff-Parkinson-White syndrome are caused by mutations in the PRKAG2 gene. Some people with these mutations also have features of hypertrophic cardiomyopathy, a form of heart disease that enlarges and weakens the heart (cardiac) muscle. The PRKAG2 gene provides instructions for making a protein that is part of an enzyme called AMP-activated protein kinase (AMPK). This enzyme helps sense and respond to energy demands within cells. It is likely involved in the development of the heart before birth, although its role in this process is unknown. Researchers are uncertain how PRKAG2 mutations lead to the development of Wolff-Parkinson-White syndrome and related heart abnormalities. Research suggests that these mutations alter the activity of AMP-activated protein kinase in the heart, although it is unclear whether the genetic changes overactivate the enzyme or reduce its activity. Studies indicate that changes in AMP-activated protein kinase activity allow a complex sugar called glycogen to build up abnormally within cardiac muscle cells. Other studies have found that altered AMP-activated protein kinase activity is related to changes in the regulation of certain ion channels in the heart. These channels, which transport positively charged atoms (ions) into and out of cardiac muscle cells, play critical roles in maintaining the heart's normal rhythm. In most cases, the cause of Wolff-Parkinson-White syndrome is unknown.
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Is Wolff-Parkinson-White syndrome inherited ?
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Most cases of Wolff-Parkinson-White syndrome occur in people with no apparent family history of the condition. These cases are described as sporadic and are not inherited. Familial Wolff-Parkinson-White syndrome accounts for only a small percentage of all cases of this condition. The familial form of the disorder typically has an autosomal dominant pattern of inheritance, which means one copy of the altered gene in each cell is sufficient to cause the condition. In most cases, a person with familial Wolff-Parkinson-White syndrome has inherited the condition from an affected parent.
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What are the treatments for Wolff-Parkinson-White syndrome ?
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These resources address the diagnosis or management of Wolff-Parkinson-White syndrome: - Genetic Testing Registry: Wolff-Parkinson-White pattern - MedlinePlus Encyclopedia: Wolff-Parkinson-White 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
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What is (are) warfarin resistance ?
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Warfarin resistance is a condition in which individuals have a high tolerance for the drug warfarin. Warfarin is an anticoagulant, which means that it thins the blood, preventing blood clots from forming. Warfarin is often prescribed to prevent blood clots in people with heart valve disease who have replacement heart valves, people with an irregular heart beat (atrial fibrillation), or those with a history of heart attack, stroke, or a prior blood clot in the deep veins of the arms or legs (deep vein thrombosis). There are two types of warfarin resistance: incomplete and complete. Those with incomplete warfarin resistance can achieve the benefits of warfarin treatment with a high dose of warfarin. Individuals with complete warfarin resistance do not respond to warfarin treatment, no matter how high the dose. If people with warfarin resistance require treatment with warfarin and take the average dose, they will remain at risk of developing a potentially harmful blood clot. Both types of warfarin resistance are related to how the body processes warfarin. In some people with warfarin resistance, their blood clotting process does not react effectively to the drug. Others with this resistance rapidly break down (metabolize) warfarin, so the medication is quickly processed by their bodies; these individuals are classified as "fast metabolizers" or "rapid metabolizers" of warfarin. The severity of these abnormal processes determines whether the warfarin resistance is complete or incomplete. Warfarin resistance does not appear to cause any health problems other than those associated with warfarin drug treatment.
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How many people are affected by warfarin resistance ?
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Warfarin resistance is thought to be a rare condition, although its prevalence is unknown.
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What are the genetic changes related to warfarin resistance ?
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Many genes are involved in the metabolism of warfarin and in determining the drug's effects in the body. Certain common changes (polymorphisms) in the VKORC1 gene account for 20 percent of the variation in warfarin metabolism due to genetic factors. Polymorphisms in other genes, some of which have not been identified, have a smaller effect on warfarin metabolism. The VKORC1 gene provides instructions for making a vitamin K epoxide reductase enzyme. The VKORC1 enzyme helps turn on (activate) clotting proteins in the pathway that forms blood clots. Warfarin prevents (inhibits) the action of VKORC1 by binding to the complex and preventing it from binding to and activating the clotting proteins, stopping clot formation. Certain VKORC1 gene polymorphisms lead to the formation of a VKORC1 enzyme with a decreased ability to bind to warfarin. This reduction in warfarin binding causes incomplete warfarin resistance and results in more warfarin being needed to inhibit the VKORC1 enzyme and stop the clotting process. If no warfarin can bind to the VKORC1 enzyme, the result is complete warfarin resistance. While changes in specific genes affect how the body reacts to warfarin, many other factors, including gender, age, weight, diet, and other medications, also play a role in the body's interaction with this drug.
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Is warfarin resistance inherited ?
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The polymorphisms associated with this condition are inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to result in warfarin resistance. However, different polymorphisms affect the activity of warfarin to varying degrees. Additionally, people who have more than one polymorphism in a gene or polymorphisms in multiple genes associated with warfarin resistance have a higher tolerance for the drug's effect or are able to process the drug more quickly.
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What are the treatments for warfarin resistance ?
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These resources address the diagnosis or management of warfarin resistance: - American Society of Hematology: Antithrombotic Therapy - MedlinePlus Drugs & Supplements: Warfarin - PharmGKB 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
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What is (are) ataxia-telangiectasia ?
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Ataxia-telangiectasia is a rare inherited disorder that affects the nervous system, immune system, and other body systems. This disorder is characterized by progressive difficulty with coordinating movements (ataxia) beginning in early childhood, usually before age 5. Affected children typically develop difficulty walking, problems with balance and hand coordination, involuntary jerking movements (chorea), muscle twitches (myoclonus), and disturbances in nerve function (neuropathy). The movement problems typically cause people to require wheelchair assistance by adolescence. People with this disorder also have slurred speech and trouble moving their eyes to look side-to-side (oculomotor apraxia). Small clusters of enlarged blood vessels called telangiectases, which occur in the eyes and on the surface of the skin, are also characteristic of this condition. Affected individuals tend to have high amounts of a protein called alpha-fetoprotein (AFP) in their blood. The level of this protein is normally increased in the bloodstream of pregnant women, but it is unknown why individuals with ataxia-telangiectasia have elevated AFP or what effects it has in these individuals. People with ataxia-telangiectasia often have a weakened immune system, and many develop chronic lung infections. They also have an increased risk of developing cancer, particularly cancer of blood-forming cells (leukemia) and cancer of immune system cells (lymphoma). Affected individuals are very sensitive to the effects of radiation exposure, including medical x-rays. The life expectancy of people with ataxia-telangiectasia varies greatly, but affected individuals typically live into early adulthood.
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How many people are affected by ataxia-telangiectasia ?
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Ataxia-telangiectasia occurs in 1 in 40,000 to 100,000 people worldwide.
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What are the genetic changes related to ataxia-telangiectasia ?
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Mutations in the ATM gene cause ataxia-telangiectasia. The ATM gene provides instructions for making a protein that helps control cell division and is involved in DNA repair. This protein plays an important role in the normal development and activity of several body systems, including the nervous system and immune system. The ATM protein assists cells in recognizing damaged or broken DNA strands and coordinates DNA repair by activating enzymes that fix the broken strands. Efficient repair of damaged DNA strands helps maintain the stability of the cell's genetic information. Mutations in the ATM gene reduce or eliminate the function of the ATM protein. Without this protein, cells become unstable and die. Cells in the part of the brain involved in coordinating movements (the cerebellum) are particularly affected by loss of the ATM protein. The loss of these brain cells causes some of the movement problems characteristic of ataxia-telangiectasia. Mutations in the ATM gene also prevent cells from responding correctly to DNA damage, which allows breaks in DNA strands to accumulate and can lead to the formation of cancerous tumors.
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Is ataxia-telangiectasia inherited ?
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Ataxia-telangiectasia is inherited in an autosomal recessive pattern, which means both copies of the ATM 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. About 1 percent of the United States population carries one mutated copy and one normal copy of the ATM gene in each cell. These individuals are called carriers. Although ATM mutation carriers do not have ataxia-telangiectasia, they are more likely than people without an ATM mutation to develop cancer; female carriers are particularly at risk for developing breast cancer. Carriers of a mutation in the ATM gene also may have an increased risk of heart disease.
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What are the treatments for ataxia-telangiectasia ?
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These resources address the diagnosis or management of ataxia-telangiectasia: - Gene Review: Gene Review: Ataxia-Telangiectasia - Genetic Testing Registry: Ataxia-telangiectasia syndrome - MedlinePlus Encyclopedia: Ataxia-Telangiectasia 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
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What is (are) familial exudative vitreoretinopathy ?
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Familial exudative vitreoretinopathy is a hereditary disorder that can cause progressive vision loss. This condition affects the retina, the specialized light-sensitive tissue that lines the back of the eye. The disorder prevents blood vessels from forming at the edges of the retina, which reduces the blood supply to this tissue. The signs and symptoms of familial exudative vitreoretinopathy vary widely, even within the same family. In many affected individuals, the retinal abnormalities never cause any vision problems. In others, a reduction in the retina's blood supply causes the retina to fold, tear, or separate from the back of the eye (retinal detachment). This retinal damage can lead to vision loss and blindness. Other eye abnormalities are also possible, including eyes that do not look in the same direction (strabismus) and a visible whiteness (leukocoria) in the normally black pupil. Some people with familial exudative vitreoretinopathy also have reduced bone mineral density, which weakens bones and increases the risk of fractures.
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How many people are affected by familial exudative vitreoretinopathy ?
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The prevalence of familial exudative vitreoretinopathy is unknown. It appears to be rare, although affected people with normal vision may never come to medical attention.
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What are the genetic changes related to familial exudative vitreoretinopathy ?
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Mutations in the FZD4, LRP5, and NDP genes can cause familial exudative vitreoretinopathy. These genes provide instructions for making proteins that participate in a chemical signaling pathway that affects the way cells and tissues develop. In particular, the proteins produced from the FZD4, LRP5, and NDP genes appear to play critical roles in the specialization of retinal cells and the establishment of a blood supply to the retina and the inner ear. The LRP5 protein also helps regulate bone formation. Mutations in the FZD4, LRP5, or NDP gene disrupt chemical signaling during early development, which interferes with the formation of blood vessels at the edges of the retina. The resulting abnormal blood supply to this tissue leads to retinal damage and vision loss in some people with familial exudative vitreoretinopathy. The eye abnormalities associated with familial exudative vitreoretinopathy tend to be similar no matter which gene is altered. However, affected individuals with LRP5 gene mutations often have reduced bone mineral density in addition to vision loss. Mutations in the other genes responsible for familial exudative vitreoretinopathy do not appear to affect bone density. In some cases, the cause of familial exudative vitreoretinopathy is unknown. Researchers believe that mutations in several as-yet-unidentified genes are responsible for the disorder in these cases.
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Is familial exudative vitreoretinopathy inherited ?
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Familial exudative vitreoretinopathy has different inheritance patterns depending on the gene involved. Most commonly, the condition results from mutations in the FZD4 or LRP5 gene and has an autosomal dominant pattern of inheritance. Autosomal dominant inheritance means one copy of the altered gene in each cell is sufficient to cause the disorder. Most people with autosomal dominant familial exudative vitreoretinopathy inherit the altered gene from a parent, although the parent may not have any signs and symptoms associated with this disorder. Familial exudative vitreoretinopathy caused by LRP5 gene mutations can also have an autosomal recessive pattern of inheritance. Autosomal recessive inheritance means both copies of the gene in each cell have mutations. The parents of an individual with autosomal recessive familial exudative vitreoretinopathy each carry one copy of the mutated gene, but they do not have the disorder. When familial exudative vitreoretinopathy is caused by mutations in the NDP gene, it has an X-linked recessive pattern of inheritance. The NDP gene is located on the X chromosome, which is one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation would have to occur in both copies of the gene to cause the disorder. Because it is unlikely that females will have two altered copies of this gene, males are affected by X-linked disorders much more frequently than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.
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What are the treatments for familial exudative vitreoretinopathy ?
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These resources address the diagnosis or management of familial exudative vitreoretinopathy: - Gene Review: Gene Review: Familial Exudative Vitreoretinopathy, Autosomal Dominant - Gene Review: Gene Review: NDP-Related Retinopathies - Genetic Testing Registry: Exudative vitreoretinopathy 1 - Genetic Testing Registry: Exudative vitreoretinopathy 3 - Genetic Testing Registry: Exudative vitreoretinopathy 4 - Genetic Testing Registry: Familial exudative vitreoretinopathy, X-linked 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
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What is (are) ALG1-congenital disorder of glycosylation ?
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ALG1-congenital disorder of glycosylation (ALG1-CDG, also known as congenital disorder of glycosylation type Ik) is an inherited disorder with varying signs and symptoms that typically develop during infancy and can affect several body systems. Individuals with ALG1-CDG often have intellectual disability, delayed development, and weak muscle tone (hypotonia). Many affected individuals develop seizures that can be difficult to treat. Individuals with ALG1-CDG may also have movement problems such as involuntary rhythmic shaking (tremor) or difficulties with movement and balance (ataxia). People with ALG1-CDG often have problems with blood clotting, which can lead to abnormal clotting or bleeding episodes. Additionally, affected individuals may produce abnormally low levels of proteins called antibodies (or immunoglobulins), particularly immunoglobulin G (IgG). Antibodies help protect the body against infection by foreign particles and germs. A reduction in antibodies can make it difficult for affected individuals to fight infections. Some people with ALG1-CDG have physical abnormalities such as a small head size (microcephaly); unusual facial features; joint deformities called contractures; long, slender fingers and toes (arachnodactyly); or unusually fleshy pads at the tips of the fingers and toes. Eye problems that may occur in people with this condition include eyes that do not point in the same direction (strabismus) or involuntary eye movements (nystagmus). Rarely, affected individuals develop vision loss. Less common abnormalities that occur in people with ALG1-CDG include respiratory problems, reduced sensation in their arms and legs (peripheral neuropathy), swelling (edema), and gastrointestinal difficulties. The signs and symptoms of ALG1-CDG are often severe, with affected individuals surviving only into infancy or childhood. However, some people with this condition are more mildly affected and survive into adulthood.
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How many people are affected by ALG1-congenital disorder of glycosylation ?
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ALG1-CDG appears to be a rare disorder; fewer than 30 affected individuals have been described in the scientific literature.
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What are the genetic changes related to ALG1-congenital disorder of glycosylation ?
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Mutations in the ALG1 gene cause ALG1-CDG. This gene provides instructions for making an enzyme that is involved in a process called glycosylation. During this process, complex chains of sugar molecules (oligosaccharides) are added to proteins and fats (lipids). Glycosylation modifies proteins and lipids so they can fully perform their functions. The enzyme produced from the ALG1 gene transfers a simple sugar called mannose to growing oligosaccharides at a particular step in the formation of the sugar chain. Once the correct number of sugar molecules are linked together, the oligosaccharide is attached to a protein or lipid. ALG1 gene mutations lead to the production of an abnormal enzyme with reduced activity. The poorly functioning enzyme cannot add mannose to sugar chains efficiently, and the resulting oligosaccharides are often incomplete. Although the short oligosaccharides can be transferred to proteins and fats, the process is not as efficient as with the full-length oligosaccharide. The wide variety of signs and symptoms in ALG1-CDG are likely due to impaired glycosylation of proteins and lipids that are needed for normal function of many organs and tissues.
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Is ALG1-congenital disorder of glycosylation inherited ?
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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.
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What are the treatments for ALG1-congenital disorder of glycosylation ?
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These resources address the diagnosis or management of ALG1-congenital disorder of glycosylation: - Gene Review: Gene Review: Congenital Disorders of N-Linked Glycosylation Pathway Overview - Genetic Testing Registry: Congenital disorder of glycosylation type 1K 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
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What is (are) Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant ?
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The Say-Barber-Biesecker-Young-Simpson (SBBYS) variant of Ohdo syndrome is a rare condition characterized by genital abnormalities in males, missing or underdeveloped kneecaps (patellae), intellectual disability, distinctive facial features, and abnormalities affecting other parts of the body. Males with the SBBYS variant of Ohdo syndrome typically have undescended testes (cryptorchidism). Females with this condition have normal genitalia. Missing or underdeveloped patellae is the most common skeletal abnormality associated with the SBBYS variant of Ohdo syndrome. Affected individuals also have joint stiffness involving the hips, knees, and ankles that can impair movement. Although joints in the lower body are stiff, joints in the arms and upper body may be unusually loose (lax). Many people with this condition have long thumbs and first (big) toes. The SBBYS variant of Ohdo syndrome is also associated with delayed development and intellectual disability, which are often severe. Many affected infants have weak muscle tone (hypotonia) that leads to breathing and feeding difficulties. The SBBYS variant of Ohdo syndrome is characterized by a mask-like, non-expressive face. Additionally, affected individuals may have distinctive facial features such as prominent cheeks, a broad nasal bridge or a nose with a rounded tip, a narrowing of the eye opening (blepharophimosis), droopy eyelids (ptosis), and abnormalities of the tear (lacrimal) glands. About one-third of affected individuals are born with an opening in the roof of the mouth called a cleft palate. The SBBYS variant of Ohdo syndrome can also be associated with heart defects and dental problems.
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How many people are affected by Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant ?
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The SBBYS variant of Ohdo syndrome is estimated to occur in fewer than 1 per million people. At least 19 cases have been reported in the medical literature.
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What are the genetic changes related to Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant ?
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The SBBYS variant of Ohdo syndrome is caused by mutations in the KAT6B gene. This gene provides instructions for making a type of enzyme called a histone acetyltransferase. These enzymes modify histones, which are structural proteins that attach (bind) to DNA and give chromosomes their shape. By adding a small molecule called an acetyl group to histones, histone acetyltransferases control the activity of certain genes. Little is known about the function of the histone acetyltransferase produced from the KAT6B gene. It appears to regulate genes that are important for early development, including development of the skeleton and nervous system. The mutations that cause the SBBYS variant of Ohdo syndrome likely prevent the production of functional histone acetyltransferase from one copy of the KAT6B gene in each cell. Studies suggest that the resulting shortage of this enzyme impairs the regulation of various genes during early development. However, it is unclear how these changes lead to the specific features of the condition.
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Is Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant inherited ?
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This condition has an autosomal dominant inheritance pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. Almost all reported cases have resulted from new mutations in the gene and have occurred in people with no history of the disorder in their family.
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What are the treatments for Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant ?
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These resources address the diagnosis or management of Ohdo syndrome, SBBYS variant: - Gene Review: Gene Review: KAT6B-Related Disorders - Genetic Testing Registry: Young Simpson 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
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What is (are) preeclampsia ?
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Preeclampsia is a complication of pregnancy in which affected women develop high blood pressure (hypertension) and can also have abnormally high levels of protein in their urine. This condition usually occurs in the last few months of pregnancy and often requires the early delivery of the infant. Many women with mild preeclampsia do not feel ill, and the problem is first detected through blood pressure and urine testing in their doctor's office. Other early features of the disorder are swelling (edema) of the face or hands and a weight gain of more than 2 pounds within a few days. More severely affected women may experience headaches, dizziness, irritability, shortness of breath, a decrease in urination, upper abdominal pain, nausea, or vomiting. Vision changes may develop, including flashing lights or spots, increased sensitivity to light (photophobia), blurry vision, or temporary blindness. In most cases, preeclampsia is mild and goes away within a few weeks after the baby is born. In severe cases, however, preeclampsia can impact the mother's organs such as the heart, liver, and kidneys and can lead to life-threatening complications. Extreme hypertension in the mother can cause bleeding in the brain (hemorrhagic stroke). The effects of high blood pressure on the brain (hypertensive encephalopathy) may also result in seizures. If seizures occur, the condition is considered to have progressed to eclampsia, which can result in coma. Without treatment to help prevent seizures, about 1 in 200 women with preeclampsia develop eclampsia. Between 10 and 20 percent of women with severe preeclampsia develop another potentially life-threatening complication called HELLP syndrome. HELLP stands for hemolysis (premature red blood cell breakdown), elevated liver enzyme levels, and low platelets (cell fragments involved in blood clotting), which are the key features of this condition. Severe preeclampsia can also affect the fetus, with impairment of blood and oxygen flow leading to growth problems or stillbirth. Infants delivered early due to preeclampsia may have complications associated with prematurity, such as breathing problems caused by underdeveloped lungs. Women who have had preeclampsia have approximately twice the lifetime risk of heart disease and stroke than do women in the general population. Researchers suggest this may be due to common factors that increase the risk of preeclampsia, heart disease, and stroke.
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How many people are affected by preeclampsia ?
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Preeclampsia is a common condition in all populations, occurring in 2 to 8 percent of pregnancies. It occurs more frequently in women of African or Hispanic descent than it does in women of European descent.
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What are the genetic changes related to preeclampsia ?
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The specific causes of preeclampsia are not well understood. In pregnancy, blood volume normally increases to support the fetus, and the mother's body must adjust to handle this extra fluid. In some women the body does not react normally to the fluid changes of pregnancy, leading to the problems with high blood pressure and urine production in the kidneys that occur in preeclampsia. The reasons for these abnormal reactions to the changes of pregnancy vary in different women and may differ depending on the stage of the pregnancy at which the condition develops. Studies suggest that preeclampsia is related to a problem with the placenta, the link between the mother's blood supply and the fetus. If there is an insufficient connection between the placenta and the arteries of the uterus, the placenta does not get enough blood. It responds by releasing a variety of substances, including molecules that affect the lining of blood vessels (the vascular endothelium). By mechanisms that are unclear, the reaction of the vascular endothelium appears to increase factors that cause the blood vessels to narrow (constrict), and decrease factors that would cause them to widen (dilate). As a result, the blood vessels constrict abnormally, causing hypertension. These blood vessel abnormalities also affect the kidneys, causing some proteins that are normally absorbed into the blood to be released in the urine instead. Researchers are studying whether variations in genes involved in fluid balance, the functioning of the vascular endothelium, or placental development affect the risk of developing preeclampsia. Many other factors likely also contribute to the risk of developing this complex disorder. These risk factors include a first pregnancy; a pregnancy with twins or higher multiples; obesity; being older than 35 or younger than 20; a history of diabetes, hypertension, or kidney disease; and preeclampsia in a previous pregnancy. Socioeconomic status and ethnicity have also been associated with preeclampsia risk. The incidence of preeclampsia in the United States has increased by 30 percent in recent years, which has been attributed in part to an increase in older mothers and multiple births resulting from the use of assisted reproductive technologies.
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Is preeclampsia inherited ?
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Most cases of preeclampsia do not seem to be inherited. The tendency to develop preeclampsia does seem to run in some families; however, the inheritance pattern is unknown.
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What are the treatments for preeclampsia ?
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These resources address the diagnosis or management of preeclampsia: - Eunice Kennedy Shriver National Institute of Child Health and Human Development: How Do Health Care Providers Diagnose Preeclampsia, Eclampsia, and HELLP syndrome? - Eunice Kennedy Shriver National Institute of Child Health and Human Development: What Are the Treatments for Preeclampsia, Eclampsia, and HELLP Syndrome? - Genetic Testing Registry: Preeclampsia/eclampsia 1 - Genetic Testing Registry: Preeclampsia/eclampsia 2 - Genetic Testing Registry: Preeclampsia/eclampsia 3 - Genetic Testing Registry: Preeclampsia/eclampsia 4 - Genetic Testing Registry: Preeclampsia/eclampsia 5 - MedlinePlus Encyclopedia: Preeclampsia Self-care 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
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What is (are) hereditary diffuse gastric cancer ?
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Hereditary diffuse gastric cancer (HDGC) is an inherited disorder that greatly increases the chance of developing a form of stomach (gastric) cancer. In this form, known as diffuse gastric cancer, there is no solid tumor. Instead cancerous (malignant) cells multiply underneath the stomach lining, making the lining thick and rigid. The invasive nature of this type of cancer makes it highly likely that these cancer cells will spread (metastasize) to other tissues, such as the liver or nearby bones. Symptoms of diffuse gastric cancer occur late in the disease and can include stomach pain, nausea, vomiting, difficulty swallowing (dysphagia), decreased appetite, and weight loss. If the cancer metastasizes to other tissues, it may lead to an enlarged liver, yellowing of the eyes and skin (jaundice), an abnormal buildup of fluid in the abdominal cavity (ascites), firm lumps under the skin, or broken bones. In HDGC, gastric cancer usually occurs in a person's late thirties or early forties, although it can develop anytime during adulthood. If diffuse gastric cancer is detected early, the survival rate is high; however, because this type of cancer is hidden underneath the stomach lining, it is usually not diagnosed until the cancer has become widely invasive. At that stage of the disease, the survival rate is approximately 20 percent. Some people with HDGC have an increased risk of developing other types of cancer, such as a form of breast cancer in women that begins in the milk-producing glands (lobular breast cancer); prostate cancer; and cancers of the colon (large intestine) and rectum, which are collectively referred to as colorectal cancer. Most people with HDGC have family members who have had one of the types of cancer associated with HDGC. In some families, all the affected members have diffuse gastric cancer. In other families, some affected members have diffuse gastric cancer and others have another associated form of cancer, such as lobular breast cancer. Frequently, HDGC-related cancers develop in individuals before the age of 50.
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How many people are affected by hereditary diffuse gastric cancer ?
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Gastric cancer is the fourth most common form of cancer worldwide, affecting 900,000 people per year. HDGC probably accounts for less than 1 percent of these cases.
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What are the genetic changes related to hereditary diffuse gastric cancer ?
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It is likely that 30 to 40 percent of individuals with HDGC have a mutation in the CDH1 gene. The CDH1 gene provides instructions for making a protein called epithelial cadherin or E-cadherin. This protein is found within the membrane that surrounds epithelial cells, which are the cells that line the surfaces and cavities of the body. E-cadherin helps neighboring cells stick to one another (cell adhesion) to form organized tissues. E-cadherin has many other functions including acting as a tumor suppressor protein, which means it prevents cells from growing and dividing too rapidly or in an uncontrolled way. People with HDGC caused by CDH1 gene mutations are born with one mutated copy of the gene in each cell. These mutations cause the production of an abnormally short, nonfunctional version of E-cadherin or alter the protein's structure. For diffuse gastric cancer to develop, a second mutation involving the other copy of the CDH1 gene must occur in the cells of the stomach lining during a person's lifetime. People who are born with one mutated copy of the CDH1 gene have a 80 percent chance of acquiring a second mutation in the other copy of the gene and developing gastric cancer in their lifetimes. When both copies of the CDH1 gene are mutated in a particular cell, that cell cannot produce any functional E-cadherin. The loss of this protein prevents it from acting as a tumor suppressor, contributing to the uncontrollable growth and division of cells. A lack of E-cadherin also impairs cell adhesion, increasing the likelihood that cancer cells will not come together to form a tumor but will invade the stomach wall and metastasize as small clusters of cancer cells into nearby tissues. These CDH1 gene mutations also lead to a 40 to 50 percent chance of lobular breast cancer in women, a slightly increased risk of prostate cancer in men, and a slightly increased risk of colorectal cancer. It is unclear why CDH1 gene mutations primarily occur in the stomach lining and these other tissues. About 60 to 70 percent of individuals with HDGC do not have an identified mutation in the CDH1 gene. The cancer-causing mechanism in these individuals is unknown.
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Is hereditary diffuse gastric cancer inherited ?
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HDGC is inherited in an autosomal dominant pattern, which means one copy of the altered CDH1 gene in each cell is sufficient to increase the risk of developing cancer. In most cases, an affected person has one parent with the condition.
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What are the treatments for hereditary diffuse gastric cancer ?
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These resources address the diagnosis or management of hereditary diffuse gastric cancer: - American Cancer Society: How is Stomach Cancer Diagnosed? - Gene Review: Gene Review: Hereditary Diffuse Gastric Cancer - Genetic Testing Registry: Hereditary diffuse gastric cancer - MedlinePlus Encyclopedia: Gastric Cancer - Memorial Sloan-Kettering Cancer Center: Early Onset and Familial Gastric Cancer Registry - National Cancer Institute: Gastric Cancer Treatment Option Overview 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
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What is (are) Jervell and Lange-Nielsen syndrome ?
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Jervell and Lange-Nielsen syndrome is a condition that causes profound hearing loss from birth and a disruption of the heart's normal rhythm (arrhythmia). This disorder is a form of long QT syndrome, which is a heart condition that causes the heart (cardiac) muscle to take longer than usual to recharge between beats. Beginning in early childhood, the irregular heartbeats increase the risk of fainting (syncope) and sudden death.
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How many people are affected by Jervell and Lange-Nielsen syndrome ?
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Jervell and Lange-Nielsen syndrome is uncommon; it affects an estimated 1.6 to 6 per 1 million people worldwide. This condition has a higher prevalence in Denmark, where it affects at least 1 in 200,000 people.
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What are the genetic changes related to Jervell and Lange-Nielsen syndrome ?
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Mutations in the KCNE1 and KCNQ1 genes cause Jervell and Lange-Nielsen syndrome. The KCNE1 and KCNQ1 genes provide instructions for making proteins that work together to form a channel across cell membranes. These channels transport positively charged potassium atoms (ions) out of cells. The movement of potassium ions through these channels is critical for maintaining the normal functions of inner ear structures and cardiac muscle. About 90 percent of cases of Jervell and Lange-Nielsen syndrome are caused by mutations in the KCNQ1 gene; KCNE1 mutations are responsible for the remaining cases. Mutations in these genes alter the usual structure and function of potassium channels or prevent the assembly of normal channels. These changes disrupt the flow of potassium ions in the inner ear and in cardiac muscle, leading to hearing loss and an irregular heart rhythm characteristic of Jervell and Lange-Nielsen syndrome.
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Is Jervell and Lange-Nielsen syndrome inherited ?
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This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of a child with an autosomal recessive disorder are not affected, but are carriers of one copy of the mutated gene. Some carriers of a KCNQ1 or KCNE1 mutation have signs and symptoms affecting the heart, but their hearing is usually normal.
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What are the treatments for Jervell and Lange-Nielsen syndrome ?
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These resources address the diagnosis or management of Jervell and Lange-Nielsen syndrome: - Gene Review: Gene Review: Jervell and Lange-Nielsen Syndrome - Genetic Testing Registry: Jervell and Lange-Nielsen syndrome - MedlinePlus Encyclopedia: Arrhythmias 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
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What is (are) acral peeling skin syndrome ?
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Acral peeling skin syndrome is a skin disorder characterized by painless peeling of the top layer of skin. The term "acral" refers to the fact that the skin peeling in this condition is most apparent on the hands and feet. Occasionally, peeling also occurs on the arms and legs. The peeling is usually evident from birth, although the condition can also begin in childhood or later in life. Skin peeling is made worse by exposure to heat, humidity and other forms of moisture, and friction. The underlying skin may be temporarily red and itchy, but it typically heals without scarring. Acral peeling skin syndrome is not associated with any other health problems.
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How many people are affected by acral peeling skin syndrome ?
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Acral peeling skin syndrome is a rare condition, with several dozen cases reported in the medical literature. However, because its signs and symptoms tend to be mild and similar to those of other skin disorders, the condition is likely underdiagnosed.
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What are the genetic changes related to acral peeling skin syndrome ?
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Acral peeling skin syndrome is caused by mutations in the TGM5 gene. This gene provides instructions for making an enzyme called transglutaminase 5, which is a component of the outer layer of skin (the epidermis). Transglutaminase 5 plays a critical role in the formation of a structure called the cornified cell envelope, which surrounds epidermal cells and helps the skin form a protective barrier between the body and its environment. TGM5 gene mutations reduce the production of transglutaminase 5 or prevent cells from making any of this protein. A shortage of transglutaminase 5 weakens the cornified cell envelope, which allows the outermost cells of the epidermis to separate easily from the underlying skin and peel off. This peeling is most noticeable on the hands and feet probably because those areas tend to be heavily exposed to moisture and friction.
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Is acral peeling skin syndrome inherited ?
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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.
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What are the treatments for acral peeling skin syndrome ?
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These resources address the diagnosis or management of acral peeling skin syndrome: - Birmingham Children's Hospital, National Health Service (UK) - Genetic Testing Registry: Peeling skin syndrome, acral 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
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What is (are) hereditary hyperekplexia ?
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Hereditary hyperekplexia is a condition in which affected infants have increased muscle tone (hypertonia) and an exaggerated startle reaction to unexpected stimuli, especially loud noises. Following the startle reaction, infants experience a brief period in which they are very rigid and unable to move. During these rigid periods, some infants stop breathing, which, if prolonged, can be fatal. This condition may explain some cases of sudden infant death syndrome (SIDS), which is a major cause of unexplained death in babies younger than 1 year. Infants with hereditary hyperekplexia have hypertonia at all times, except when they are sleeping. Other signs and symptoms of hereditary hyperekplexia can include muscle twitches when falling asleep (hypnagogic myoclonus) and movements of the arms or legs while asleep. Some infants, when tapped on the nose, extend their head forward and have spasms of the limb and neck muscles. Rarely, infants with hereditary hyperekplexia experience recurrent seizures (epilepsy). The signs and symptoms of hereditary hyperekplexia typically fade by age 1. However, older individuals with hereditary hyperekplexia may still startle easily and have periods of rigidity, which can cause them to fall down. Some individuals with this condition have a low tolerance for crowded places and loud noises. Some affected people have persistent limb movements during sleep. Affected individuals who have epilepsy have the disorder throughout their lives.
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How many people are affected by hereditary hyperekplexia ?
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The exact prevalence of hereditary hyperekplexia is unknown. This condition has been identified in more than 70 families worldwide.
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What are the genetic changes related to hereditary hyperekplexia ?
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At least five genes are associated with hereditary hyperekplexia. Most of these genes provide instructions for producing proteins that are found in nerve cells (neurons). They play a role in how neurons respond to a molecule called glycine. This molecule acts as a neurotransmitter, which is a chemical messenger that transmits signals in the nervous system. Gene mutations that cause hereditary hyperekplexia disrupt normal cell signaling in the spinal cord and the part of the brain that is connected to the spinal cord (the brainstem). Approximately 80 percent of cases of hereditary hyperekplexia are caused by mutations in the GLRA1 gene. The GLRA1 gene provides instructions for making one part, the alpha ()1 subunit, of the glycine receptor protein. GLRA1 gene mutations lead to the production of a receptor that cannot properly respond to glycine. As a result, glycine is less able to transmit signals in the spinal cord and brainstem. Mutations in the other four genes account for a small percentage of all cases of hereditary hyperekplexia. A disruption in cell signaling caused by mutations in the five genes associated with hereditary hyperekplexia is thought to cause the abnormal muscle movements, exaggerated startle reaction, and other symptoms characteristic of this disorder.
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Is hereditary hyperekplexia inherited ?
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Hereditary hyperekplexia has different inheritance patterns. This condition can be inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In some cases, an affected person inherits the mutation from one affected parent. Other cases may result from new mutations in the gene. These cases occur in people with no history of the disorder in their family. Hereditary hyperekplexia can also be 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 disorder typically each carry one copy of the altered gene, but do not show signs and symptoms of the disorder. Rarely, hereditary hyperekplexia is inherited in an X-linked pattern. In these cases, 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. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.
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What are the treatments for hereditary hyperekplexia ?
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These resources address the diagnosis or management of hereditary hyperekplexia: - Gene Review: Gene Review: Hyperekplexia - Genetic Testing Registry: Early infantile epileptic encephalopathy 8 - Genetic Testing Registry: Hyperekplexia hereditary 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
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What is (are) abdominal wall defect ?
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An abdominal wall defect is an opening in the abdomen through which various abdominal organs can protrude. This opening varies in size and can usually be diagnosed early in fetal development, typically between the tenth and fourteenth weeks of pregnancy. There are two main types of abdominal wall defects: omphalocele and gastroschisis. Omphalocele is an opening in the center of the abdominal wall where the umbilical cord meets the abdomen. Organs (typically the intestines, stomach, and liver) protrude through the opening into the umbilical cord and are covered by the same protective membrane that covers the umbilical cord. Gastroschisis is a defect in the abdominal wall, usually to the right of the umbilical cord, through which the large and small intestines protrude (although other organs may sometimes bulge out). There is no membrane covering the exposed organs in gastroschisis. Fetuses with omphalocele may grow slowly before birth (intrauterine growth retardation) and they may be born prematurely. Individuals with omphalocele frequently have multiple birth defects, such as a congenital heart defect. Additionally, underdevelopment of the lungs is often associated with omphalocele because the abdominal organs normally provide a framework for chest wall growth. When those organs are misplaced, the chest wall does not form properly, providing a smaller than normal space for the lungs to develop. As a result, many infants with omphalocele have respiratory insufficiency and may need to be supported with a machine to help them breathe (mechanical ventilation). Rarely, affected individuals who have breathing problems in infancy experience recurrent lung infections or asthma later in life. Affected infants often have gastrointestinal problems including a backflow of stomach acids into the esophagus (gastroesophageal reflux) and feeding difficulty; these problems can persist even after treatment of omphalocele. Large omphaloceles or those associated with multiple additional health problems are more often associated with fetal death than cases in which omphalocele occurs alone (isolated). Omphalocele is a feature of many genetic syndromes. Nearly half of individuals with omphalocele have a condition caused by an extra copy of one of the chromosomes in each of their cells (trisomy). Up to one-third of people born with omphalocele have a genetic condition called Beckwith-Wiedemann syndrome. Affected individuals may have additional signs and symptoms associated with these genetic conditions. Individuals who have gastroschisis rarely have other birth defects and seldom have chromosome abnormalities or a genetic condition. Most affected individuals experience intrauterine growth retardation and are small at birth; many affected infants are born prematurely. With gastroschisis, the protruding organs are not covered by a protective membrane and are susceptible to damage due to direct contact with amniotic fluid in the womb. Components of the amniotic fluid may trigger immune responses and inflammatory reactions against the intestines that can damage the tissue. Constriction around exposed organs at the abdominal wall opening late in fetal development may also contribute to organ injury. Intestinal damage causes impairment of the muscle contractions that move food through the digestive tract (peristalsis) in most children with gastroschisis. In these individuals, peristalsis usually improves in a few months and intestinal muscle contractions normalize. Rarely, children with gastroschisis have a narrowing or absence of a portion of intestine (intestinal atresia) or twisting of the intestine. After birth, these intestinal malformations can lead to problems with digestive function, further loss of intestinal tissue, and a condition called short bowel syndrome that occurs when areas of the small intestine are missing, causing dehydration and poor absorption of nutrients. Depending on the severity of the condition, intravenous feedings (parenteral nutrition) may be required. The health of an individual with gastroschisis depends largely on how damaged his or her intestine was before birth. When the abdominal wall defect is repaired and normal intestinal function is recovered, the vast majority of affected individuals have no health problems related to the repaired defect later in life.
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How many people are affected by abdominal wall defect ?
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Abdominal wall defects are uncommon. Omphalocele affects an estimated 2 to 2.5 in 10,000 newborns. Approximately 2 to 6 in 10,000 newborns are affected by gastroschisis, although researchers have observed that this malformation is becoming more common. Abdominal wall defects are more common among pregnancies that do not survive to term (miscarriages and stillbirths).
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What are the genetic changes related to abdominal wall defect ?
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No genetic mutations are known to cause an abdominal wall defect. Multiple genetic and environmental factors likely influence the development of this disorder. Omphalocele and gastroschisis are caused by different errors in fetal development. Omphalocele occurs during an error in digestive tract development. During the formation of the abdominal cavity in the sixth to tenth weeks of fetal development, the intestines normally protrude into the umbilical cord but recede back into the abdomen as development continues. Omphalocele occurs when the intestines do not recede back into the abdomen, but remain in the umbilical cord. Other abdominal organs can also protrude through this opening, resulting in the varied organ involvement that occurs in omphalocele. The error that leads to gastroschisis formation is unknown. It is thought to be either a disruption in the blood flow to the digestive tract or a lack of development or injury to gastrointestinal tissue early in fetal development. For reasons that are unknown, women under the age of 20 are at the greatest risk of having a baby with gastroschisis. Other risk factors in pregnancy may include taking medications that constrict the blood vessels (called vasoconstrictive drugs) or smoking, although these risk factors have not been confirmed.
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Is abdominal wall defect inherited ?
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Most cases of abdominal wall defect are sporadic, which means they occur in people with no history of the disorder in their family. Multiple genetic and environmental factors likely play a part in determining the risk of developing this disorder. When an abdominal wall defect, most often omphalocele, is a feature of a genetic condition, it is inherited in the pattern of that condition.
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What are the treatments for abdominal wall defect ?
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These resources address the diagnosis or management of abdominal wall defect: - Cincinnati Children's Hospital: Gastroschisis - Cincinnati Children's Hospital: Omphalocele - Cleveland Clinic: Omphalocele - Genetic Testing Registry: Congenital omphalocele - Great Ormond Street Hospital for Children (UK): Gastroschisis - MedlinePlus Encyclopedia: Gastroschisis Repair - MedlinePlus Encyclopedia: Gastroschisis Repair--Series (images) - MedlinePlus Encyclopedia: Omphalocele Repair - MedlinePlus Encyclopedia: Omphalocele Repair--Series (images) - Seattle Children's Hospital: Gastroschisis Treatment Options - Seattle Children's Hospital: Omphalocele Treatment Options - The Children's Hospital of Philadelphia: Diagnosis and Treatment of Gastroschisis - The Children's Hospital of Philadelphia: Overview and Treatment of Omphalocele - University of California, San Francisco Fetal Treatment Center: Gastroschisis - University of California, San Francisco Fetal Treatment Center: Omphalocele 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
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What is (are) very long-chain acyl-CoA dehydrogenase deficiency ?
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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.
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How many people are affected by very long-chain acyl-CoA dehydrogenase deficiency ?
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VLCAD deficiency is estimated to affect 1 in 40,000 to 120,000 people.
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