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What are the genetic changes related to mucopolysaccharidosis type IV ?
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Mutations in the GALNS and GLB1 genes cause MPS IV. These genes provide instructions for producing enzymes involved in the breakdown of large sugar molecules called glycosaminoglycans (GAGs). GAGs were originally called mucopolysaccharides, which is where this condition gets its name. When MPS IV is caused by mutations in the GALNS gene it is called MPS IV type A (MPS IVA), and when it is caused by mutations in the GLB1 gene it is called MPS IV type B (MPS IVB). In general, the two types of MPS IV cannot be distinguished by their signs and symptoms. Mutations in the GALNS and GLB1 genes reduce or completely eliminate the activity of the enzymes produced from these genes. Without these enzymes, GAGs accumulate within cells, specifically inside the lysosomes. Lysosomes are compartments in the cell that break down and recycle different types of molecules. Conditions such as MPS IV that cause molecules to build up inside the lysosomes are called lysosomal storage disorders. In MPS IV, GAGs accumulate to toxic levels in many tissues and organs, particularly in the bones. The accumulation of GAGs causes the bone deformities in this disorder. Researchers believe that the buildup of GAGs may also cause the features of MPS IV by interfering with the functions of other proteins inside lysosomes and disrupting the movement of molecules inside the cell.
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Is mucopolysaccharidosis type IV 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 mucopolysaccharidosis type IV ?
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These resources address the diagnosis or management of mucopolysaccharidosis type IV: - Genetic Testing Registry: Morquio syndrome - Genetic Testing Registry: Mucopolysaccharidosis, MPS-IV-A - Genetic Testing Registry: Mucopolysaccharidosis, MPS-IV-B - MedlinePlus Encyclopedia: Morquio 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) phenylketonuria ?
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Phenylketonuria (commonly known as PKU) is an inherited disorder that increases the levels of a substance called phenylalanine in the blood. Phenylalanine is a building block of proteins (an amino acid) that is obtained through the diet. It is found in all proteins and in some artificial sweeteners. If PKU is not treated, phenylalanine can build up to harmful levels in the body, causing intellectual disability and other serious health problems. The signs and symptoms of PKU vary from mild to severe. The most severe form of this disorder is known as classic PKU. Infants with classic PKU appear normal until they are a few months old. Without treatment, these children develop permanent intellectual disability. Seizures, delayed development, behavioral problems, and psychiatric disorders are also common. Untreated individuals may have a musty or mouse-like odor as a side effect of excess phenylalanine in the body. Children with classic PKU tend to have lighter skin and hair than unaffected family members and are also likely to have skin disorders such as eczema. Less severe forms of this condition, sometimes called variant PKU and non-PKU hyperphenylalaninemia, have a smaller risk of brain damage. People with very mild cases may not require treatment with a low-phenylalanine diet. Babies born to mothers with PKU and uncontrolled phenylalanine levels (women who no longer follow a low-phenylalanine diet) have a significant risk of intellectual disability because they are exposed to very high levels of phenylalanine before birth. These infants may also have a low birth weight and grow more slowly than other children. Other characteristic medical problems include heart defects or other heart problems, an abnormally small head size (microcephaly), and behavioral problems. Women with PKU and uncontrolled phenylalanine levels also have an increased risk of pregnancy loss.
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How many people are affected by phenylketonuria ?
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The occurrence of PKU varies among ethnic groups and geographic regions worldwide. In the United States, PKU occurs in 1 in 10,000 to 15,000 newborns. Most cases of PKU are detected shortly after birth by newborn screening, and treatment is started promptly. As a result, the severe signs and symptoms of classic PKU are rarely seen.
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What are the genetic changes related to phenylketonuria ?
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Mutations in the PAH gene cause phenylketonuria. The PAH gene provides instructions for making an enzyme called phenylalanine hydroxylase. This enzyme converts the amino acid phenylalanine to other important compounds in the body. If gene mutations reduce the activity of phenylalanine hydroxylase, phenylalanine from the diet is not processed effectively. As a result, this amino acid can build up to toxic levels in the blood and other tissues. Because nerve cells in the brain are particularly sensitive to phenylalanine levels, excessive amounts of this substance can cause brain damage. Classic PKU, the most severe form of the disorder, occurs when phenylalanine hydroxylase activity is severely reduced or absent. People with untreated classic PKU have levels of phenylalanine high enough to cause severe brain damage and other serious medical problems. Mutations in the PAH gene that allow the enzyme to retain some activity result in milder versions of this condition, such as variant PKU or non-PKU hyperphenylalaninemia. Changes in other genes may influence the severity of PKU, but little is known about these additional genetic factors.
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Is phenylketonuria 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 phenylketonuria ?
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These resources address the diagnosis or management of phenylketonuria: - Baby's First Test - Gene Review: Gene Review: Phenylalanine Hydroxylase Deficiency - Genetic Testing Registry: Phenylketonuria - MedlinePlus Encyclopedia: Phenylketonuria - MedlinePlus Encyclopedia: Serum Phenylalanine Screening 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) ovarian cancer ?
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Ovarian cancer is a disease that affects women. In this form of cancer, certain cells in the ovary become abnormal and multiply uncontrollably to form a tumor. The ovaries are the female reproductive organs in which egg cells are produced. In about 90 percent of cases, ovarian cancer occurs after age 40, and most cases occur after age 60. The most common form of ovarian cancer begins in epithelial cells, which are the cells that line the surfaces and cavities of the body. These cancers can arise in the epithelial cells on the surface of the ovary. However, researchers suggest that many or even most ovarian cancers begin in epithelial cells on the fringes (fimbriae) at the end of one of the fallopian tubes, and the cancerous cells migrate to the ovary. Cancer can also begin in epithelial cells that form the lining of the abdomen (the peritoneum). This form of cancer, called primary peritoneal cancer, resembles epithelial ovarian cancer in its origin, symptoms, progression, and treatment. Primary peritoneal cancer often spreads to the ovaries. It can also occur even if the ovaries have been removed. Because cancers that begin in the ovaries, fallopian tubes, and peritoneum are so similar and spread easily from one of these structures to the others, they are often difficult to distinguish. These cancers are so closely related that they are generally considered collectively by experts. In about 10 percent of cases, ovarian cancer develops not in epithelial cells but in germ cells, which are precursors to egg cells, or in hormone-producing ovarian cells called granulosa cells. In its early stages, ovarian cancer usually does not cause noticeable symptoms. As the cancer progresses, signs and symptoms can include pain or a feeling of heaviness in the pelvis or lower abdomen, bloating, feeling full quickly when eating, back pain, vaginal bleeding between menstrual periods or after menopause, or changes in urinary or bowel habits. However, these changes can occur as part of many different conditions. Having one or more of these symptoms does not mean that a woman has ovarian cancer. In some cases, cancerous tumors can invade surrounding tissue and spread to other parts of the body. If ovarian cancer spreads, cancerous tumors most often appear in the abdominal cavity or on the surfaces of nearby organs such as the bladder or colon. Tumors that begin at one site and then spread to other areas of the body are called metastatic cancers. Some ovarian cancers cluster in families. These cancers are described as hereditary and are associated with inherited gene mutations. Hereditary ovarian cancers tend to develop earlier in life than non-inherited (sporadic) cases. Because it is often diagnosed at a late stage, ovarian cancer can be difficult to treat; it leads to the deaths of about 140,000 women annually, more than any other gynecological cancer. However, when it is diagnosed and treated early, the 5-year survival rate is high.
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How many people are affected by ovarian cancer ?
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Ovarian cancer affects about 12 in 100,000 women per year.
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What are the genetic changes related to ovarian cancer ?
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Cancers occur when a buildup of mutations in critical genesthose that control cell growth and division or repair damaged DNAallow cells to grow and divide uncontrollably to form a tumor. Most cases of ovarian cancer are sporadic; in these cases the associated genetic changes are acquired during a person's lifetime and are present only in certain cells in the ovary. These changes, which are called somatic mutations, are not inherited. Somatic mutations in the TP53 gene occur in almost half of all ovarian cancers. The protein produced from this gene is described as a tumor suppressor because it helps keep cells from growing and dividing too fast or in an uncontrolled way. Most of these mutations change single protein building blocks (amino acids) in the p53 protein, which reduces or eliminates the protein's tumor suppressor function. Because the altered protein is less able to regulate cell growth and division, a cancerous tumor may develop. Somatic mutations in many other genes have also been found in ovarian cancer cells. In hereditary ovarian cancer, the associated genetic changes are passed down within a family. These changes, classified as germline mutations, are present in all the body's cells. In people with germline mutations, other inherited and somatic gene changes, together with environmental and lifestyle factors, also influence whether a woman will develop ovarian cancer. Germline mutations are involved in more than one-fifth of ovarian cancer cases. Between 65 and 85 percent of these mutations are in the BRCA1 or BRCA2 gene. These gene mutations are described as "high penetrance" because they are associated with a high risk of developing ovarian cancer, breast cancer, and several other types of cancer in women. Compared to a 1.6 percent lifetime risk of developing ovarian cancer for women in the total population, the lifetime risk in women with a BRCA1 gene mutation is 40 to 60 percent, and the lifetime risk in women with a BRCA2 gene mutation is 20 to 35 percent. Men with mutations in these genes also have an increased risk of developing several forms of cancer. The proteins produced from the BRCA1 and BRCA2 genes are tumor suppressors that are involved in fixing damaged DNA, which helps to maintain the stability of a cell's genetic information. Mutations in these genes impair DNA repair, allowing potentially damaging mutations to persist in DNA. As these defects accumulate, they can trigger cells to grow and divide without control or order to form a tumor. A significantly increased risk of ovarian cancer is also a feature of certain rare genetic syndromes, including a disorder called Lynch syndrome. Lynch syndrome is most often associated with mutations in the MLH1 or MSH2 gene and accounts for between 10 and 15 percent of hereditary ovarian cancers. Other rare genetic syndromes may also be associated with an increased risk of ovarian cancer. The proteins produced from the genes associated with these syndromes act as tumor suppressors. Mutations in any of these genes can allow cells to grow and divide unchecked, leading to the development of a cancerous tumor. Like BRCA1 and BRCA2, these genes are considered "high penetrance" because mutations greatly increase a person's chance of developing cancer. In addition to ovarian cancer, mutations in these genes increase the risk of several other types of cancer in both men and women. Germline mutations in dozens of other genes have been studied as possible risk factors for ovarian cancer. These genes are described as "low penetrance" or "moderate penetrance" because changes in each of these genes appear to make only a small or moderate contribution to overall ovarian cancer risk. Some of these genes provide instructions for making proteins that interact with the proteins produced from the BRCA1 or BRCA2 genes. Others act through different pathways. Researchers suspect that the combined influence of variations in these genes may significantly impact a person's risk of developing ovarian cancer. In many families, the genetic changes associated with hereditary ovarian cancer are unknown. Identifying additional genetic risk factors for ovarian cancer is an active area of medical research. In addition to genetic changes, researchers have identified many personal and environmental factors that contribute to a woman's risk of developing ovarian cancer. These factors include age, ethnic background, and hormonal and reproductive factors. A history of ovarian cancer in closely related family members is also an important risk factor, particularly if the cancer occurred in early adulthood.
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Is ovarian cancer inherited ?
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Most cases of ovarian cancer are not caused by inherited genetic factors. These cancers are associated with somatic mutations that are acquired during a person's lifetime, and they do not cluster in families. A predisposition to cancer caused by a germline mutation is usually inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to increase a person's chance of developing cancer. Although ovarian cancer occurs only in women, the mutated gene can be inherited from either the mother or the father. It is important to note that people inherit an increased likelihood of developing cancer, not the disease itself. Not all people who inherit mutations in these genes will ultimately develop cancer. In many cases of ovarian cancer that clusters in families, the genetic basis for the disease and the mechanism of inheritance are unclear.
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What are the treatments for ovarian cancer ?
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These resources address the diagnosis or management of ovarian cancer: - Dana-Farber Cancer Institute - Familial Ovarian Cancer Registry - Fred Hutchinson Cancer Research Center - Gene Review: Gene Review: BRCA1 and BRCA2 Hereditary Breast/Ovarian Cancer - Genetic Testing Registry: Hereditary breast and ovarian cancer syndrome - Genetic Testing Registry: Ovarian cancer - Genomics Education Programme (UK): Hereditary Breast and Ovarian Cancer - M.D. Anderson Cancer Center - MedlinePlus Encyclopedia: BRCA1 and BRCA2 Gene Testing - MedlinePlus Encyclopedia: CA-125 Blood Test - Memorial Sloan-Kettering Cancer Center 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) cytochrome P450 oxidoreductase deficiency ?
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Cytochrome P450 oxidoreductase deficiency is a disorder of hormone production. This condition specifically affects steroid hormones, which are needed for normal development and reproduction. The hormonal changes associated with cytochrome P450 oxidoreductase deficiency can affect the development of the reproductive system, skeleton, and other parts of the body. These signs and symptoms are usually present at birth or become apparent in early childhood. The signs and symptoms of cytochrome P450 oxidoreductase deficiency vary from mild to severe. Signs and symptoms of mild cases can include a failure to begin menstruation by age 16 (primary amenorrhea), an inability to have biological children (infertility) in both men and women, and a condition called polycystic ovarian syndrome (PCOS). PCOS is characterized by a hormonal imbalance in women that can lead to irregular menstruation, acne, excess body hair (hirsutism), and weight gain. People with moderate cases of cytochrome P450 oxidoreductase deficiency may have external genitalia that do not look clearly male or female (ambiguous genitalia), and they may have infertility. People with moderate cytochrome P450 oxidoreductase deficiency usually do not have skeletal abnormalities. The severe form of cytochrome P450 oxidoreductase deficiency is sometimes called Antley-Bixler syndrome with genital anomalies and disordered steroidogenesis. Hormonal changes in affected males and females lead to the development of ambiguous genitalia or other genital abnormalities, as well as infertility. Severe cases are also characterized by skeletal abnormalities, particularly involving bones of the head and face. These include premature fusion of the skull bones (craniosynostosis), a flattened mid-face, a prominent forehead, and low-set ears. Other skeletal abnormalities can include joint deformities (contractures) that limit movement; unusually long, slender fingers (arachnodactyly); bowing of the thigh bones; and radiohumeral synostosis, which is a bone abnormality that locks the elbows in a bent position. A blockage of the nasal passages (choanal atresia), intellectual disability, and delayed development are also associated with the severe form of the disorder. Some women who are pregnant with fetuses affected by cytochrome P450 oxidoreductase deficiency experience mild symptoms of the disorder even though they themselves do not have the disorder. They may develop excessive body hair growth (hirsutism), acne, and a deep voice. These changes go away soon after delivery.
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How many people are affected by cytochrome P450 oxidoreductase deficiency ?
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The prevalence of cytochrome P450 oxidoreductase deficiency is unknown. About 65 cases have been reported worldwide. Researchers suspect that cytochrome P450 oxidoreductase deficiency is underdiagnosed and that mild cases of this disorder may be relatively common. Because the signs and symptoms can be difficult to detect, people with mild cytochrome P450 oxidoreductase deficiency may never come to medical attention.
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What are the genetic changes related to cytochrome P450 oxidoreductase deficiency ?
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Cytochrome P450 oxidoreductase deficiency is caused by mutations in the POR gene. This gene provides instructions for making the enzyme cytochrome P450 oxidoreductase, which plays a critical role in the formation of steroid hormones. This group of hormones includes testosterone and estrogen, which are essential for normal sexual development and reproduction; corticosteroids, which are involved in the body's response to stress; and aldosterone, which helps regulate the body's salt and water balance. Mutations in the POR gene reduce the activity of cytochrome P450 oxidoreductase, which disrupts the production of steroid hormones. Changes in sex hormones such as testosterone and estrogen lead to problems with sexual development before birth and at puberty. In a woman who is pregnant with an affected fetus, abnormal levels of sex hormones in the fetus may cause her to have mild, temporary signs and symptoms of cytochrome P450 oxidoreductase deficiency. Cytochrome P450 oxidoreductase is also needed for the production of cholesterol. This substance has many essential functions both before and after birth, including roles in the production of steroid hormones and in the formation and growth of bones. Mutations in the POR gene can disrupt the production of cholesterol, which likely impairs normal bone formation in the severe form of cytochrome P450 oxidoreductase deficiency. Studies suggest that a molecule called retinoic acid also plays a role in the skeletal abnormalities found in severe cases. The breakdown of retinoic acid requires cytochrome P450 oxidoreductase; if a shortage of cytochrome P450 oxidoreductase prevents retinoic acid from being broken down, the resulting excess of that molecule can stimulate the abnormal growth and fusion of bones. The skeletal abnormalities found in the severe form of this disorder can also result from mutations in another gene, FGFR2. Some researchers use the name Antley-Bixler syndrome to describe these features, whether they are caused by mutations in the POR gene or in the FGFR2 gene. Others use the name Antley-Bixler syndrome with genital anomalies and disordered steroidogenesis for cases caused by POR gene mutations, reserving the name Antley-Bixler syndrome for cases caused by FGFR2 gene mutations.
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Is cytochrome P450 oxidoreductase deficiency 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 cytochrome P450 oxidoreductase deficiency ?
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These resources address the diagnosis or management of cytochrome P450 oxidoreductase deficiency: - Gene Review: Gene Review: Cytochrome P450 Oxidoreductase Deficiency - Genetic Testing Registry: Antley-Bixler syndrome with genital anomalies and disordered steroidogenesis - MedlinePlus Encyclopedia: Ambiguous Genitalia - MedlinePlus Encyclopedia: Craniosynostosis 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) 9q22.3 microdeletion ?
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9q22.3 microdeletion is a chromosomal change in which a small piece of chromosome 9 is deleted in each cell. The deletion occurs on the long (q) arm of the chromosome in a region designated q22.3. This chromosomal change is associated with delayed development, intellectual disability, certain physical abnormalities, and the characteristic features of a genetic condition called Gorlin syndrome. Many individuals with a 9q22.3 microdeletion have delayed development, particularly affecting the development of motor skills such as sitting, standing, and walking. In some people, the delays are temporary and improve in childhood. More severely affected individuals have permanent developmental disabilities along with intellectual impairment and learning problems. Rarely, seizures have been reported in people with a 9q22.3 microdeletion. About 20 percent of people with a 9q22.3 microdeletion experience overgrowth (macrosomia), which results in increased height and weight compared to unaffected peers. The macrosomia often begins before birth and continues into childhood. Other physical changes that can be associated with a 9q22.3 microdeletion include the premature fusion of certain bones in the skull (metopic craniosynostosis) and a buildup of fluid in the brain (hydrocephalus). Affected individuals can also have distinctive facial features such as a prominent forehead with vertical skin creases, upward- or downward-slanting eyes, a short nose, and a long space between the nose and upper lip (philtrum). 9q22.3 microdeletions also cause the characteristic features of Gorlin syndrome (also known as nevoid basal cell carcinoma syndrome). This genetic condition affects many areas of the body and increases the risk of developing various cancerous and noncancerous tumors. In people with Gorlin syndrome, the type of cancer diagnosed most often is basal cell carcinoma, which is the most common form of skin cancer. Most people with this condition also develop noncancerous (benign) tumors of the jaw, called keratocystic odontogenic tumors, which can cause facial swelling and tooth displacement. Other types of tumors that occur more often in people with Gorlin syndrome include a form of childhood brain cancer called a medulloblastoma and a type of benign tumor called a fibroma that occurs in the heart or in a woman's ovaries. Other features of Gorlin syndrome include small depressions (pits) in the skin of the palms of the hands and soles of the feet; an unusually large head size (macrocephaly) with a prominent forehead; and skeletal abnormalities involving the spine, ribs, or skull.
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How many people are affected by 9q22.3 microdeletion ?
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9q22.3 microdeletion appears to be a rare chromosomal change. About three dozen affected individuals have been reported in the medical literature.
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What are the genetic changes related to 9q22.3 microdeletion ?
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People with a 9q22.3 microdeletion are missing a sequence of at least 352,000 DNA building blocks (base pairs), also written as 352 kilobases (kb), in the q22.3 region of chromosome 9. This 352-kb segment is known as the minimum critical region because it is the smallest deletion that has been found to cause the signs and symptoms described above. 9q22.3 microdeletions can also be much larger; the largest reported deletion includes 20.5 million base pairs (20.5 Mb). 9q22.3 microdeletion affects one of the two copies of chromosome 9 in each cell. People with a 9q22.3 microdeletion are missing from two to more than 270 genes on chromosome 9. All known 9q22.3 microdeletions include the PTCH1 gene. The protein produced from this gene, patched-1, acts as a tumor suppressor, which means it keeps cells from growing and dividing (proliferating) too rapidly or in an uncontrolled way. Researchers believe that many of the features associated with 9q22.3 microdeletions, particularly the signs and symptoms of Gorlin syndrome, result from a loss of the PTCH1 gene. When this gene is missing, patched-1 is not available to suppress cell proliferation. As a result, cells divide uncontrollably to form the tumors that are characteristic of Gorlin syndrome. Other signs and symptoms related to 9q22.3 microdeletions probably result from the loss of additional genes in the q22.3 region. Researchers are working to determine which missing genes contribute to the other features associated with the deletion.
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Is 9q22.3 microdeletion inherited ?
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9q22.3 microdeletions are inherited in an autosomal dominant pattern, which means that missing genetic material from one of the two copies of chromosome 9 in each cell is sufficient to cause delayed development, intellectual disability, and the features of Gorlin syndrome. A 9q22.3 microdeletion most often occurs in people whose parents do not carry the chromosomal change. In these cases, the deletion occurs as a random (de novo) event during the formation of reproductive cells (eggs or sperm) in a parent or in early embryonic development. De novo chromosomal changes occur in people with no history of the disorder in their family. Less commonly, individuals with a 9q22.3 microdeletion inherit the chromosomal change from an unaffected parent. In these cases, the parent carries a chromosomal rearrangement called a balanced translocation, in which a segment of chromosome 9 has traded places with a segment of another chromosome. No genetic material is gained or lost in a balanced translocation, so these chromosomal changes usually do not cause any health problems. However, translocations can become unbalanced as they are passed to the next generation. People who inherit a 9q22.3 microdeletion receive an unbalanced translocation that deletes genetic material from one copy of the q22.3 region of chromosome 9 in each cell. Having one missing copy of the PTCH1 gene in each cell is enough to cause the features of Gorlin syndrome that are present early in life, including macrocephaly and skeletal abnormalities. For basal cell carcinomas and other tumors to develop, a mutation in the other copy of the PTCH1 gene must also occur in certain cells during the person's lifetime. Most people who are born with one missing copy of the PTCH1 gene eventually acquire a mutation in the other copy of the gene in some cells and consequently develop various types of tumors.
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What are the treatments for 9q22.3 microdeletion ?
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These resources address the diagnosis or management of 9q22.3 microdeletion: - Gene Review: Gene Review: 9q22.3 Microdeletion - Gene Review: Gene Review: Nevoid Basal Cell Carcinoma Syndrome - Genetic Testing Registry: Gorlin syndrome - MedlinePlus Encyclopedia: Basal Cell Nevus 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) primary sclerosing cholangitis ?
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Primary sclerosing cholangitis is a condition that affects the bile ducts. These ducts carry bile (a fluid that helps to digest fats) from the liver, where bile is produced, to the gallbladder, where it is stored, and to the small intestine, where it aids in digestion. Primary sclerosing cholangitis occurs because of inflammation in the bile ducts (cholangitis) that leads to scarring (sclerosis) and narrowing of the ducts. As a result, bile cannot be released to the gallbladder and small intestine, and it builds up in the liver. Primary sclerosing cholangitis is usually diagnosed around age 40, and for unknown reasons, it affects men twice as often as women. Many people have no signs or symptoms of the condition when they are diagnosed, but routine blood tests reveal liver problems. When apparent, the earliest signs and symptoms of primary sclerosing cholangitis include extreme tiredness (fatigue), discomfort in the abdomen, and severe itchiness (pruritus). As the condition worsens, affected individuals may develop yellowing of the skin and whites of the eyes (jaundice) and an enlarged spleen (splenomegaly). Eventually, the buildup of bile damages the liver cells, causing chronic liver disease (cirrhosis) and liver failure. Without bile available to digest them, fats pass through the body. As a result, weight loss and shortages of vitamins that are absorbed with and stored in fats (fat-soluble vitamins) can occur. A fat-soluble vitamin called vitamin D helps absorb calcium and helps bones harden, and lack of this vitamin can cause thinning of the bones (osteoporosis) in people with primary sclerosing cholangitis. Primary sclerosing cholangitis is often associated with another condition called inflammatory bowel disease, which is characterized by inflammation of the intestines that causes open sores (ulcers) in the intestines and abdominal pain. However, the reason for this link is unclear. Approximately 70 percent of people with primary sclerosing cholangitis have inflammatory bowel disease, most commonly a form of the condition known as ulcerative colitis. In addition, people with primary sclerosing cholangitis are more likely to have an autoimmune disorder, such as type 1 diabetes, celiac disease, or thyroid disease, than people without the condition. Autoimmune disorders occur when the immune system malfunctions and attacks the body's tissues and organs. People with primary sclerosing cholangitis also have an increased risk of developing cancer, particularly cancer of the bile ducts (cholangiocarcinoma).
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How many people are affected by primary sclerosing cholangitis ?
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An estimated 1 in 10,000 people have primary sclerosing cholangitis, and the condition is diagnosed in approximately 1 in 100,000 people per year worldwide.
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What are the genetic changes related to primary sclerosing cholangitis ?
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Primary sclerosing cholangitis is thought to arise from a combination of genetic and environmental factors. Researchers believe that genetic changes play a role in this condition because it often occurs in several members of a family and because immediate family members of someone with primary sclerosing cholangitis have an increased risk of developing the condition. It is likely that specific genetic variations increase a person's risk of developing primary sclerosing cholangitis, and then exposure to certain environmental factors triggers the disorder. However, the genetic changes that increase susceptibility and the environmental triggers remain unclear. There is evidence that variations in certain genes involved in immune function influence the risk of developing primary sclerosing cholangitis. The most commonly associated genes belong to a family of genes called the human leukocyte antigen (HLA) complex. The HLA complex helps the immune system distinguish the body's own proteins from proteins made by foreign invaders (such as viruses and bacteria). Each HLA gene has many different normal variations, allowing each person's immune system to react to a wide range of foreign proteins. Specific variations of several HLA genes seem to be present more often in people with primary sclerosing cholangitis than in people who do not have the disorder. These variations may dysregulate the body's immune response, leading to the inflammation of the bile ducts in people with primary sclerosing cholangitis. However, the mechanism is not well understood. Researchers are also studying variations in other genes related to the body's immune function to understand how they contribute to the risk of developing this condition.
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Is primary sclerosing cholangitis inherited ?
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The inheritance pattern of primary sclerosing cholangitis is unknown because many genetic and environmental factors are likely to be involved. This condition tends to cluster in families, however, and having an affected family member is a risk factor for developing the disease.
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What are the treatments for primary sclerosing cholangitis ?
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These resources address the diagnosis or management of primary sclerosing cholangitis: - American Liver Foundation: Primary Sclerosing Cholangitis (PSC) - Genetic Testing Registry: Primary sclerosing cholangitis - MedlinePlus Encyclopedia: Sclerosing Cholangitis - University of California San Francisco Medical Center 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) hyperparathyroidism-jaw tumor syndrome ?
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Hyperparathyroidism-jaw tumor syndrome is a condition characterized by overactivity of the parathyroid glands (hyperparathyroidism). The four parathyroid glands are located in the neck and secrete a hormone that regulates the body's use of calcium. Hyperparathyroidism disrupts the normal balance of calcium in the blood, which can lead to kidney stones, thinning of the bones (osteoporosis), nausea, vomiting, high blood pressure (hypertension), weakness, and fatigue. In people with hyperthyroidism-jaw tumor syndrome, hyperparathyroidism is caused by tumors that form in the parathyroid glands. Typically only one of the four parathyroid glands is affected, but in some people, tumors are found in more than one gland. The tumors are usually noncancerous (benign), in which case they are called adenomas. Approximately 15 percent of people with hyperparathyroidism-jaw tumor syndrome develop a cancerous tumor called parathyroid carcinoma. People with hyperparathyroidism-jaw tumor syndrome may also have a type of benign tumor called a fibroma in the jaw. Even though jaw tumors are specified in the name of this condition, it is estimated that only 25 to 50 percent of affected individuals have this symptom. Other tumors, both benign and cancerous, are often seen in hyperparathyroidism-jaw tumor syndrome. For example, tumors of the uterus occur in about 75 percent of women with this condition. The kidneys are affected in about 20 percent of people with hyperparathyroidism-jaw tumor syndrome. Benign kidney cysts are the most common kidney feature, but a rare tumor called Wilms tumor and other types of kidney tumor have also been found.
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How many people are affected by hyperparathyroidism-jaw tumor syndrome ?
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The exact prevalence of hyperparathyroidism-jaw tumor syndrome is unknown. Approximately 200 cases have been reported in the medical literature.
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What are the genetic changes related to hyperparathyroidism-jaw tumor syndrome ?
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Mutations in the CDC73 gene (also known as the HRPT2 gene) cause hyperparathyroidism-jaw tumor syndrome. The CDC73 gene provides instructions for making a protein called parafibromin. This protein is found throughout the body and is likely involved in gene transcription, which is the first step in protein production. Parafibromin is also thought to play a role in cell growth and division (proliferation), either promoting or inhibiting cell proliferation depending on signals within the cell. CDC73 gene mutations cause hyperparathyroidism-jaw tumor syndrome by reducing the amount of functional parafibromin that is produced. Most of these mutations result in a parafibromin protein that is abnormally short and nonfunctional. Without functional parafibromin, cell proliferation is not properly regulated. Uncontrolled cell division can lead to the formation of tumors. It is unknown why only certain tissues seem to be affected by changes in parafibromin. Some people with hyperparathyroidism-jaw tumor syndrome do not have identified mutations in the CDC73 gene. The cause of the condition in these individuals is unknown.
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Is hyperparathyroidism-jaw tumor syndrome 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.
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What are the treatments for hyperparathyroidism-jaw tumor syndrome ?
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These resources address the diagnosis or management of hyperparathyroidism-jaw tumor syndrome: - Gene Review: Gene Review: CDC73-Related Disorders - Genetic Testing Registry: Hyperparathyroidism 2 - MedlinePlus Encyclopedia: Hyperparathyroidism These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
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What is (are) palmoplantar keratoderma with deafness ?
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Palmoplantar keratoderma with deafness is a disorder characterized by skin abnormalities and hearing loss. Affected individuals develop unusually thick skin on the palms of the hands and soles of the feet (palmoplantar keratoderma) beginning in childhood. Hearing loss ranges from mild to profound. It begins in early childhood and gets worse over time. Affected individuals have particular trouble hearing high-pitched sounds. The signs and symptoms of this disorder may vary even within the same family, with some individuals developing only skin abnormalities and others developing only hearing loss.
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How many people are affected by palmoplantar keratoderma with deafness ?
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Palmoplantar keratoderma with deafness is a rare disorder; its prevalence is unknown. At least 10 affected families have been identified.
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What are the genetic changes related to palmoplantar keratoderma with deafness ?
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Palmoplantar keratoderma with deafness can be caused by mutations in the GJB2 or MT-TS1 genes. The GJB2 gene provides instructions for making a protein called gap junction beta 2, more commonly known as connexin 26. Connexin 26 is a member of the connexin protein family. Connexin proteins form channels called gap junctions that permit the transport of nutrients, charged atoms (ions), and signaling molecules between neighboring cells that are in contact with each other. Gap junctions made with connexin 26 transport potassium ions and certain small molecules. Connexin 26 is found in cells throughout the body, including the inner ear and the skin. In the inner ear, channels made from connexin 26 are found in a snail-shaped structure called the cochlea. These channels may help to maintain the proper level of potassium ions required for the conversion of sound waves to electrical nerve impulses. This conversion is essential for normal hearing. In addition, connexin 26 may be involved in the maturation of certain cells in the cochlea. Connexin 26 also plays a role in the growth, maturation, and stability of the outermost layer of skin (the epidermis). The GJB2 gene mutations that cause palmoplantar keratoderma with deafness change single protein building blocks (amino acids) in connexin 26. The altered protein probably disrupts the function of normal connexin 26 in cells, and may interfere with the function of other connexin proteins. This disruption could affect skin growth and also impair hearing by disturbing the conversion of sound waves to nerve impulses. Palmoplantar keratoderma with deafness can also be caused by a mutation in the MT-TS1 gene. This gene provides instructions for making a particular type of RNA, a molecule that is a chemical cousin of DNA. This type of RNA, called transfer RNA (tRNA), helps assemble amino acids into full-length, functioning proteins. The MT-TS1 gene provides instructions for a specific form of tRNA that is designated as tRNASer(UCN). This molecule attaches to a particular amino acid, serine (Ser), and inserts it into the appropriate locations in many different proteins. The tRNASer(UCN) molecule is present only in cellular structures called mitochondria. These structures convert energy from food into a form that cells can use. Through a process called oxidative phosphorylation, mitochondria use oxygen, simple sugars, and fatty acids to create adenosine triphosphate (ATP), the cell's main energy source. The tRNASer(UCN) molecule is involved in the assembly of proteins that carry out oxidative phosphorylation. The MT-TS1 gene mutation that causes palmoplantar keratoderma with deafness leads to reduced levels of tRNASer(UCN) to assemble proteins within mitochondria. Reduced production of proteins needed for oxidative phosphorylation may impair the ability of mitochondria to make ATP. Researchers have not determined why the effects of the mutation are limited to cells in the inner ear and the skin in this condition.
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Is palmoplantar keratoderma with deafness inherited ?
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Palmoplantar keratoderma with deafness can have different inheritance patterns. When this disorder is caused by GJB2 gene mutations, it 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. When palmoplantar keratoderma with deafness is caused by mutations in the MT-TS1 gene, it is inherited in a mitochondrial pattern, which is also known as maternal inheritance. This pattern of inheritance applies to genes contained in mitochondrial DNA (mtDNA). Because egg cells, but not sperm cells, contribute mitochondria to the developing embryo, children can only inherit disorders resulting from mtDNA mutations from their mother. These disorders can appear in every generation of a family and can affect both males and females, but fathers do not pass traits associated with changes in mtDNA to their children.
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What are the treatments for palmoplantar keratoderma with deafness ?
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These resources address the diagnosis or management of palmoplantar keratoderma with deafness: - Foundation for Ichthyosis and Related Skin Types: Palmoplantar Keratodermas - Genetic Testing Registry: Keratoderma palmoplantar deafness 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) Simpson-Golabi-Behmel syndrome ?
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Simpson-Golabi-Behmel syndrome is a condition that affects many parts of the body and occurs primarily in males. This condition is classified as an overgrowth syndrome, which means that affected infants are considerably larger than normal at birth (macrosomia) and continue to grow and gain weight at an unusual rate. The other signs and symptoms of Simpson-Golabi-Behmel syndrome vary widely. The most severe cases are life-threatening before birth or in infancy, whereas people with milder cases often live into adulthood. People with Simpson-Golabi-Behmel syndrome have distinctive facial features including widely spaced eyes (ocular hypertelorism), an unusually large mouth (macrostomia), a large tongue (macroglossia) that may have a deep groove or furrow down the middle, a broad nose with an upturned tip, and abnormalities affecting the roof of the mouth (the palate). The facial features are often described as "coarse" in older children and adults with this condition. Other features of Simpson-Golabi-Behmel syndrome involve the chest and abdomen. Affected infants may be born with one or more extra nipples, an abnormal opening in the muscle covering the abdomen (diastasis recti), a soft out-pouching around the belly-button (an umbilical hernia), or a hole in the diaphragm (a diaphragmatic hernia) that allows the stomach and intestines to move into the chest and crowd the developing heart and lungs. Simpson-Golabi-Behmel syndrome can also cause heart defects, malformed or abnormally large kidneys, an enlarged liver and spleen (hepatosplenomegaly), and skeletal abnormalities. Additionally, the syndrome can affect the development of the gastrointestinal system, urinary system, and genitalia. Some people with this condition have mild to severe intellectual disability, while others have normal intelligence. About 10 percent of people with Simpson-Golabi-Behmel syndrome develop cancerous or noncancerous tumors in early childhood. The most common tumors are a rare form of kidney cancer called Wilms tumor and a cancerous tumor called a neuroblastoma that arises in developing nerve cells.
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How many people are affected by Simpson-Golabi-Behmel syndrome ?
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The incidence of Simpson-Golabi-Behmel syndrome is unknown. At least 130 people worldwide have been diagnosed with this disorder.
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What are the genetic changes related to Simpson-Golabi-Behmel syndrome ?
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Mutations in the GPC3 gene are responsible for some cases of Simpson-Golabi-Behmel syndrome. This gene provides instructions for making a protein called glypican 3, which is involved in the regulation of cell growth and division (cell proliferation). Researchers believe that the GPC3 protein can also cause certain cells to self-destruct (undergo apoptosis) when they are no longer needed, which can help establish the body's shape. GPC3 mutations can delete part or all of the gene, or alter the structure of glypican 3. These mutations prevent the protein from performing its usual functions, which may contribute to an increased rate of cell growth and cell division starting before birth. It is unclear, however, how a shortage of functional glypican 3 causes overgrowth of the entire body and the other abnormalities characteristic of Simpson-Golabi-Behmel syndrome. Some individuals with Simpson-Golabi-Behmel syndrome do not have identified mutations in the GPC3 gene. In these cases, the cause of the condition is unknown.
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Is Simpson-Golabi-Behmel syndrome inherited ?
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This condition is inherited in an X-linked 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 each cell. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. Because females have two copies of the X chromosome, one altered copy of the gene in each cell usually leads to less severe symptoms in females than in males, or it may cause no symptoms at all. Some females who have one altered copy of the GPC3 gene have distinctive facial features including an upturned nose, a wide mouth, and a prominent chin. Their fingernails may be malformed and they can have extra nipples. Skeletal abnormalities, including extra spinal bones (vertebrae), are also possible in affected females. Other females who carry one altered copy of the GPC3 gene do not have these features or any other medical problems associated with Simpson-Golabi-Behmel syndrome.
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What are the treatments for Simpson-Golabi-Behmel syndrome ?
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These resources address the diagnosis or management of Simpson-Golabi-Behmel syndrome: - Gene Review: Gene Review: Simpson-Golabi-Behmel Syndrome Type 1 - Genetic Testing Registry: Simpson-Golabi-Behmel syndrome - MedlinePlus Encyclopedia: Diastasis Recti - MedlinePlus Encyclopedia: Macrosomia 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) mitochondrial complex III deficiency ?
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Mitochondrial complex III deficiency is a genetic condition that can affect several parts of the body, including the brain, kidneys, liver, heart, and the muscles used for movement (skeletal muscles). Signs and symptoms of mitochondrial complex III deficiency usually begin in infancy but can appear later. The severity of mitochondrial complex III deficiency varies widely among affected individuals. People who are mildly affected tend to have muscle weakness (myopathy) and extreme tiredness (fatigue), particularly during exercise (exercise intolerance). More severely affected individuals have problems with multiple body systems, such as liver disease that can lead to liver failure, kidney abnormalities (tubulopathy), and brain dysfunction (encephalopathy). Encephalopathy can cause delayed development of mental and motor skills (psychomotor delay), movement problems, weak muscle tone (hypotonia), and difficulty with communication. Some affected individuals have a form of heart disease called cardiomyopathy, which can lead to heart failure. Most people with mitochondrial complex III deficiency have a buildup of a chemical called lactic acid in the body (lactic acidosis). Some affected individuals also have buildup of molecules called ketones (ketoacidosis) or high blood sugar levels (hyperglycemia). Abnormally high levels of these chemicals in the body can be life-threatening. Mitochondrial complex III deficiency can be fatal in childhood, although individuals with mild signs and symptoms can survive into adolescence or adulthood.
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How many people are affected by mitochondrial complex III deficiency ?
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The prevalence of mitochondrial complex III deficiency is unknown, although the condition is thought to be rare.
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What are the genetic changes related to mitochondrial complex III deficiency ?
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Mitochondrial complex III deficiency can be caused by mutations in one of several genes. The proteins produced from these genes either are a part of or help assemble a group of proteins called complex III. The two most commonly mutated genes involved in mitochondrial complex III deficiency are MT-CYB and BCS1L. It is likely that genes that have not been identified are also involved in this condition. Cytochrome b, produced from the MT-CYB gene, is one component of complex III, and the protein produced from the BCS1L gene is critical for the formation of the complex. Complex III is found in cell structures called mitochondria, which convert the energy from food into a form that cells can use. Complex III is one of several complexes that carry out a multistep process called oxidative phosphorylation, through which cells derive much of their energy. As a byproduct of its action in oxidative phosphorylation, complex III produces reactive oxygen species, which are harmful molecules that can damage DNA and tissues. MT-CYB and BCS1L gene mutations impair the formation of complex III molecules. As a result, complex III activity and oxidative phosphorylation are reduced. Researchers believe that impaired oxidative phosphorylation can lead to cell death by reducing the amount of energy available in the cell. It is thought that tissues and organs that require a lot of energy, such as the brain, liver, kidneys, and skeletal muscles, are most affected by a reduction in oxidative phosphorylation. In addition, for unknown reasons, BCS1L gene mutations lead to increased overall production of reactive oxygen species, although production by complex III is reduced. Damage from reduced energy and from reactive oxygen species likely contributes to the signs and symptoms of mitochondrial complex III deficiency. Unlike most genes, the MT-CYB gene is found in DNA located in mitochondria, called mitochondrial DNA (mtDNA). This location may help explain why some people have more severe features of the condition than others. Most of the body's cells contain thousands of mitochondria, each with one or more copies of mtDNA. These cells can have a mix of mitochondria containing mutated and unmutated DNA (heteroplasmy). When caused by MT-CYB gene mutations, the severity of mitochondrial complex III deficiency is thought to be associated with the percentage of mitochondria with the gene mutation. The other genes known to be involved in this condition are found in DNA packaged in chromosomes within the cell nucleus (nuclear DNA). It is not clear why the severity of the condition varies in people with mutations in these other genes.
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Is mitochondrial complex III deficiency inherited ?
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Mitochondrial complex III deficiency is usually 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. In some cases caused by mutations in the MT-CYB gene, the condition is not inherited; it is caused by new mutations in the gene that occur in people with no history of the condition in their family. Other cases caused by mutations in the MT-CYB gene are inherited in a mitochondrial pattern, which is also known as maternal inheritance. This pattern of inheritance applies to genes contained in mtDNA. Because egg cells, but not sperm cells, contribute mitochondria to the developing embryo, children can only inherit disorders resulting from mtDNA mutations from their mother. These disorders can appear in every generation of a family and can affect both males and females, but fathers do not pass traits associated with changes in mtDNA to their children.
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What are the treatments for mitochondrial complex III deficiency ?
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These resources address the diagnosis or management of mitochondrial complex III deficiency: - Gene Review: Gene Review: Mitochondrial Disorders Overview - Genetic Testing Registry: MITOCHONDRIAL COMPLEX III DEFICIENCY, NUCLEAR TYPE 6 - Genetic Testing Registry: MITOCHONDRIAL COMPLEX III DEFICIENCY, NUCLEAR TYPE 7 - Genetic Testing Registry: MITOCHONDRIAL COMPLEX III DEFICIENCY, NUCLEAR TYPE 8 - Genetic Testing Registry: Mitochondrial complex III deficiency - Genetic Testing Registry: Mitochondrial complex III deficiency, nuclear type 2 - Genetic Testing Registry: Mitochondrial complex III deficiency, nuclear type 3 - Genetic Testing Registry: Mitochondrial complex III deficiency, nuclear type 4 - Genetic Testing Registry: Mitochondrial complex III deficiency, nuclear type 5 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) isolated Pierre Robin sequence ?
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Pierre Robin sequence is a set of abnormalities affecting the head and face, consisting of a small lower jaw (micrognathia), a tongue that is placed further back than normal (glossoptosis), and an opening in the roof of the mouth (a cleft palate). This condition is described as a "sequence" because one of its features, an underdeveloped lower jaw (mandible), sets off a sequence of events before birth that cause the other signs and symptoms. Specifically, having an abnormally small jaw affects placement of the tongue and formation of the palate, leading to glossoptosis and cleft palate. The combination of features characteristic of Pierre Robin sequence can lead to difficulty breathing and problems eating early in life. As a result, some affected babies have an inability to grow and gain weight at the expected rate (failure to thrive). In some children with Pierre Robin sequence, growth of the mandible catches up, and these individuals have normal-sized chins. Some people have Pierre Robin sequence as part of a syndrome that affects other organs and tissues in the body, such as campomelic dysplasia or Stickler syndrome. These instances are described as syndromic. When Pierre Robin sequence occurs by itself, it is described as nonsyndromic or isolated. Approximately 20 to 40 percent of cases of Pierre Robin sequence are isolated.
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How many people are affected by isolated Pierre Robin sequence ?
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Isolated Pierre Robin sequence affects an estimated 1 in 8,500 to 14,000 people.
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What are the genetic changes related to isolated Pierre Robin sequence ?
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Changes in the DNA near the SOX9 gene are the most common genetic cause of isolated Pierre Robin sequence. It is likely that changes in other genes, some of which have not been identified, also cause isolated Pierre Robin sequence. The SOX9 gene provides instructions for making a protein that plays a critical role in the formation of many different tissues and organs during embryonic development. The SOX9 protein regulates the activity of other genes, especially those that are important for development of the skeleton, including the mandible. The genetic changes associated with isolated Pierre Robin sequence occur near the SOX9 gene. These abnormalities are thought to disrupt regions of DNA called enhancers that normally regulate the activity of the SOX9 gene, reducing SOX9 gene activity. As a result, the SOX9 protein cannot properly control the genes essential for normal development of the lower jaw, causing micrognathia, and consequently, glossoptosis and cleft palate.
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Is isolated Pierre Robin sequence inherited ?
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Isolated Pierre Robin sequence is usually not inherited. It typically results from new genetic changes and occurs in people with no history of the disorder in their family. When the condition is inherited, it follows an autosomal dominant pattern, which means one copy of the altered DNA in each cell is sufficient to cause the disorder.
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What are the treatments for isolated Pierre Robin sequence ?
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These resources address the diagnosis or management of isolated Pierre Robin sequence: - Boston Children's Hospital: Cleft Lip and Cleft Palate Treatment and Care - Genetic Testing Registry: Robin sequence - Seattle Children's Hospital: Robin Sequence Treatments 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) 3-hydroxyacyl-CoA dehydrogenase deficiency ?
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3-hydroxyacyl-CoA dehydrogenase deficiency is an inherited condition that prevents the body from converting certain fats to energy, particularly during prolonged periods without food (fasting). Initial signs and symptoms of this disorder typically occur during infancy or early childhood and can include poor appetite, vomiting, diarrhea, and lack of energy (lethargy). Affected individuals can also have muscle weakness (hypotonia), liver problems, low blood sugar (hypoglycemia), and abnormally high levels of insulin (hyperinsulinism). Insulin controls the amount of sugar that moves from the blood into cells for conversion to energy. Individuals with 3-hydroxyacyl-CoA dehydrogenase deficiency are also at risk for complications such as seizures, life-threatening heart and breathing problems, coma, and sudden death. This condition may explain some cases of sudden infant death syndrome (SIDS), which is defined as unexplained death in babies younger than 1 year. Problems related to 3-hydroxyacyl-CoA dehydrogenase deficiency can be triggered by periods of fasting or by illnesses such as viral infections. 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 3-hydroxyacyl-CoA dehydrogenase deficiency ?
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The exact incidence of 3-hydroxyacyl-CoA dehydrogenase deficiency is unknown; it has been reported in only a small number of people worldwide.
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What are the genetic changes related to 3-hydroxyacyl-CoA dehydrogenase deficiency ?
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Mutations in the HADH gene cause 3-hydroxyacyl-CoA dehydrogenase deficiency. The HADH gene provides instructions for making an enzyme called 3-hydroxyacyl-CoA dehydrogenase. Normally, through a process called fatty acid oxidation, several enzymes work in a step-wise fashion to break down (metabolize) fats and convert them to energy. The 3-hydroxyacyl-CoA dehydrogenase enzyme is required for a step that metabolizes groups of fats called medium-chain fatty acids and short-chain fatty acids. Mutations in the HADH gene lead to a shortage of 3-hydroxyacyl-CoA dehydrogenase. Medium-chain and short-chain fatty acids cannot be metabolized properly without sufficient levels of this enzyme. As a result, these fatty acids are not converted to energy, which can lead to characteristic features of 3-hydroxyacyl-CoA dehydrogenase deficiency, such as lethargy and hypoglycemia. Medium-chain and short-chain fatty acids that are not broken down can build up in tissues and damage the liver, heart, and muscles, causing serious complications. Conditions that disrupt the metabolism of fatty acids, including 3-hydroxyacyl-CoA dehydrogenase deficiency, are known as fatty acid oxidation disorders.
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Is 3-hydroxyacyl-CoA dehydrogenase deficiency 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 3-hydroxyacyl-CoA dehydrogenase deficiency ?
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These resources address the diagnosis or management of 3-hydroxyacyl-CoA dehydrogenase deficiency: - Baby's First Test - Genetic Testing Registry: Deficiency of 3-hydroxyacyl-CoA dehydrogenase - United Mitochondrial Disease Foundation: Treatments & Therapies 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) aniridia ?
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Aniridia is an eye disorder characterized by a complete or partial absence of the colored part of the eye (the iris). These iris abnormalities may cause the pupils to be abnormal or misshapen. Aniridia can cause reduction in the sharpness of vision (visual acuity) and increased sensitivity to light (photophobia). People with aniridia can also have other eye problems. Increased pressure in the eye (glaucoma) typically appears in late childhood or early adolescence. Clouding of the lens of the eye (cataracts), occur in 50 percent to 85 percent of people with aniridia. In about 10 percent of affected people, the structures that carry information from the eyes to the brain (optic nerves) are underdeveloped. Individuals with aniridia may also have involuntary eye movements (nystagmus) or underdevelopment of the region at the back of the eye responsible for sharp central vision (foveal hypoplasia). Many of these eye problems contribute to progressive vision loss in affected individuals. The severity of symptoms is typically the same in both eyes. Rarely, people with aniridia have behavioral problems, developmental delay, and problems detecting odors.
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How many people are affected by aniridia ?
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Aniridia occurs in 1 in 50,000 to 100,000 newborns worldwide.
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What are the genetic changes related to aniridia ?
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Aniridia is caused by mutations in the PAX6 gene. The PAX6 gene provides instructions for making a protein that is involved in the early development of the eyes, brain and spinal cord (central nervous system), and the pancreas. Within the brain, the PAX6 protein is involved in the development of a specialized group of brain cells that process smell (the olfactory bulb). The PAX6 protein attaches (binds) to specific regions of DNA and regulates the activity of other genes. On the basis of this role, the PAX6 protein is called a transcription factor. Following birth, the PAX6 protein regulates several genes that likely contribute to the maintenance of different eye structures. Mutations in the PAX6 gene result in the production of a nonfunctional PAX6 protein that is unable to bind to DNA and regulate the activity of other genes. A lack of functional PAX6 protein disrupts the formation of the eyes during embryonic development.
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Is aniridia inherited ?
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Aniridia 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 approximately two-thirds of cases, an affected person inherits the mutation from one affected parent. The remaining one-third of 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 aniridia ?
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These resources address the diagnosis or management of aniridia: - Gene Review: Gene Review: Aniridia - Genetic Testing Registry: Congenital aniridia 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) fatty acid hydroxylase-associated neurodegeneration ?
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Fatty acid hydroxylase-associated neurodegeneration (FAHN) is a progressive disorder of the nervous system (neurodegeneration) characterized by problems with movement and vision that begin during childhood or adolescence. Changes in the way a person walks (gait) and frequent falls are usually the first noticeable signs of FAHN. Affected individuals gradually develop extreme muscle stiffness (spasticity) and exaggerated reflexes. They typically have involuntary muscle cramping (dystonia), problems with coordination and balance (ataxia), or both. The movement problems worsen over time, and some people with this condition eventually require wheelchair assistance. People with FAHN often develop vision problems, which occur due to deterioration (atrophy) of the nerves that carry information from the eyes to the brain (the optic nerves) and difficulties with the muscles that control eye movement. Affected individuals may have a loss of sharp vision (reduced visual acuity), decreased field of vision, impaired color perception, eyes that do not look in the same direction (strabismus), rapid involuntary eye movements (nystagmus), or difficulty moving the eyes intentionally (supranuclear gaze palsy). Speech impairment (dysarthria) also occurs in FAHN, and severely affected individuals may lose the ability to speak. People with this disorder may also have difficulty chewing or swallowing (dysphagia). In severe cases, they may develop malnutrition and require a feeding tube. The swallowing difficulties can lead to a bacterial lung infection called aspiration pneumonia, which can be life-threatening. As the disorder progresses, some affected individuals experience seizures and a decline in intellectual function. Magnetic resonance imaging (MRI) of the brain in people with FAHN shows signs of iron accumulation, especially in an area of the brain called the globus pallidus, which is involved in regulating movement. Similar patterns of iron accumulation are seen in certain other neurological disorders such as infantile neuroaxonal dystrophy and pantothenate kinase-associated neurodegeneration. All these conditions belong to a class of disorders called neurodegeneration with brain iron accumulation (NBIA).
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How many people are affected by fatty acid hydroxylase-associated neurodegeneration ?
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FAHN is a rare disorder; only a few dozen cases have been reported.
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What are the genetic changes related to fatty acid hydroxylase-associated neurodegeneration ?
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Mutations in the FA2H gene cause FAHN. The FA2H gene provides instructions for making an enzyme called fatty acid 2-hydroxylase. This enzyme modifies fatty acids, which are building blocks used to make fats (lipids). Specifically, fatty acid 2-hydroxylase adds a single oxygen atom to a hydrogen atom at a particular point on a fatty acid to create a 2-hydroxylated fatty acid. Certain 2-hydroxylated fatty acids are important in forming normal myelin; myelin is the protective covering that insulates nerves and ensures the rapid transmission of nerve impulses. The part of the brain and spinal cord that contains myelin is called white matter. The FA2H gene mutations that cause FAHN reduce or eliminate the function of the fatty acid 2-hydroxylase enzyme. Reduction of this enzyme's function may result in abnormal myelin that is prone to deterioration (demyelination), leading to a loss of white matter (leukodystrophy). Leukodystrophy is likely involved in the development of the movement problems and other neurological abnormalities that occur in FAHN. Iron accumulation in the brain is probably also involved, although it is unclear how FA2H gene mutations lead to the buildup of iron. People with FA2H gene mutations and some of the movement problems seen in FAHN were once classified as having a separate disorder called spastic paraplegia 35. People with mutations in this gene resulting in intellectual decline and optic nerve atrophy were said to have a disorder called FA2H-related leukodystrophy. However, these conditions are now generally considered to be forms of FAHN.
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Is fatty acid hydroxylase-associated neurodegeneration 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 fatty acid hydroxylase-associated neurodegeneration ?
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These resources address the diagnosis or management of fatty acid hydroxylase-associated neurodegeneration: - Gene Review: Gene Review: Fatty Acid Hydroxylase-Associated Neurodegeneration - Genetic Testing Registry: Spastic paraplegia 35 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) systemic scleroderma ?
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Systemic scleroderma is an autoimmune disorder that affects the skin and internal organs. Autoimmune disorders occur when the immune system malfunctions and attacks the body's own tissues and organs. The word "scleroderma" means hard skin in Greek, and the condition is characterized by the buildup of scar tissue (fibrosis) in the skin and other organs. The condition is also called systemic sclerosis because the fibrosis can affect organs other than the skin. Fibrosis is due to the excess production of a tough protein called collagen, which normally strengthens and supports connective tissues throughout the body. The signs and symptoms of systemic scleroderma usually begin with episodes of Raynaud phenomenon, which can occur weeks to years before fibrosis. In Raynaud phenomenon, the fingers and toes of affected individuals turn white or blue in response to cold temperature or other stresses. This effect occurs because of problems with the small vessels that carry blood to the extremities. Another early sign of systemic scleroderma is puffy or swollen hands before thickening and hardening of the skin due to fibrosis. Skin thickening usually occurs first in the fingers (called sclerodactyly) and may also involve the hands and face. In addition, people with systemic scleroderma often have open sores (ulcers) on their fingers, painful bumps under the skin (calcinosis), or small clusters of enlarged blood vessels just under the skin (telangiectasia). Fibrosis can also affect internal organs and can lead to impairment or failure of the affected organs. The most commonly affected organs are the esophagus, heart, lungs, and kidneys. Internal organ involvement may be signaled by heartburn, difficulty swallowing (dysphagia), high blood pressure (hypertension), kidney problems, shortness of breath, diarrhea, or impairment of the muscle contractions that move food through the digestive tract (intestinal pseudo-obstruction). There are three types of systemic scleroderma, defined by the tissues affected in the disorder. In one type of systemic scleroderma, known as limited cutaneous systemic scleroderma, fibrosis usually affects only the hands, arms, and face. Limited cutaneous systemic scleroderma used to be known as CREST syndrome, which is named for the common features of the condition: calcinosis, Raynaud phenomenon, esophageal motility dysfunction, sclerodactyly, and telangiectasia. In another type of systemic scleroderma, known as diffuse cutaneous systemic scleroderma, the fibrosis affects large areas of skin, including the torso and the upper arms and legs, and often involves internal organs. In diffuse cutaneous systemic scleroderma, the condition worsens quickly and organ damage occurs earlier than in other types of the condition. In the third type of systemic scleroderma, called systemic sclerosis sine scleroderma ("sine" means without in Latin), fibrosis affects one or more internal organs but not the skin. Approximately 15 percent to 25 percent of people with features of systemic scleroderma also have signs and symptoms of another condition that affects connective tissue, such as polymyositis, dermatomyositis, rheumatoid arthritis, Sjgren syndrome, or systemic lupus erythematosus. The combination of systemic scleroderma with other connective tissue abnormalities is known as scleroderma overlap syndrome.
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How many people are affected by systemic scleroderma ?
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The prevalence of systemic scleroderma is estimated to range from 50 to 300 cases per 1 million people. For reasons that are unknown, women are four times more likely to develop the condition than men.
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What are the genetic changes related to systemic scleroderma ?
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Researchers have identified variations in several genes that may influence the risk of developing systemic scleroderma. The most commonly associated genes belong to a family of genes called the human leukocyte antigen (HLA) complex. The HLA complex helps the immune system distinguish the body's own proteins from proteins made by foreign invaders (such as viruses and bacteria). Each HLA gene has many different normal variations, allowing each person's immune system to react to a wide range of foreign proteins. Specific normal variations of several HLA genes seem to affect the risk of developing systemic scleroderma. Normal variations in other genes related to the body's immune function, such as IRF5 and STAT4, are also associated with an increased risk of developing systemic scleroderma. Variations in the IRF5 gene are specifically associated with diffuse cutaneous systemic scleroderma, and a variation in the STAT4 gene is associated with limited cutaneous systemic scleroderma. The IRF5 and STAT4 genes both play a role in initiating an immune response when the body detects a foreign invader (pathogen) such as a virus. It is not known how variations in the associated genes contribute to the increased risk of systemic scleroderma. Variations in multiple genes may work together to increase the risk of developing the condition, and researchers are working to identify and confirm other genes associated with increased risk. In addition, a combination of genetic and environmental factors seems to play a role in developing systemic scleroderma.
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Is systemic scleroderma inherited ?
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Most cases of systemic scleroderma are sporadic, which means they occur in people with no history of the condition in their family. However, some people with systemic scleroderma have close relatives with other autoimmune disorders. A small percentage of all cases of systemic scleroderma have been reported to run in families; however, the condition does not have a clear pattern of inheritance. Multiple genetic and environmental factors likely play a part in determining the risk of developing this condition. As a result, inheriting a genetic variation linked with systemic scleroderma does not mean that a person will develop the condition.
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What are the treatments for systemic scleroderma ?
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These resources address the diagnosis or management of systemic scleroderma: - Cedars-Sinai Medical Center - Genetic Testing Registry: Scleroderma, familial progressive - University of Maryland Medical Center 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) distal myopathy 2 ?
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Distal myopathy 2 is a condition characterized by weakness of specific muscles that begins in adulthood. It is a form of muscular dystrophy that specifically involves muscles in the throat, lower legs, and forearms. Muscles farther from the center of the body, like the muscles of the lower legs and forearms, are known as distal muscles. Muscle weakness in the ankles is usually the first symptom of distal myopathy 2. The weakness can also affect muscles in the hands, wrists, and shoulders. At first, the muscle weakness may be on only one side of the body, but both sides are eventually involved. This muscle weakness can slowly worsen and make actions like walking and lifting the fingers difficult. Another characteristic feature of distal myopathy 2 is weakness of the vocal cords and throat. This weakness initially causes the voice to sound weak or breathy (hypophonic). Eventually, the voice becomes gurgling, hoarse, and nasal. The weakness can also cause difficulty swallowing (dysphagia).
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How many people are affected by distal myopathy 2 ?
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The prevalence of distal myopathy 2 is unknown. At least two families with the condition have been described in the scientific literature.
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What are the genetic changes related to distal myopathy 2 ?
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A mutation in the MATR3 gene has been identified in people with distal myopathy 2. This gene provides instructions for making a protein called matrin 3, which is found in the nucleus of the cell as part of the nuclear matrix. The nuclear matrix is a network of proteins that provides structural support for the nucleus and aids in several important nuclear functions. The function of the matrin 3 protein is unknown. This protein can attach to (bind) RNA, which is a chemical cousin of DNA. Some studies indicate that matrin 3 binds and stabilizes a type of RNA called messenger RNA (mRNA), which provides the genetic blueprint for proteins. Matrin 3 may also bind certain abnormal RNAs that might lead to nonfunctional or harmful proteins, thereby blocking the formation of such proteins. Other studies suggest that the matrin 3 protein may be involved in cell survival. The MATR3 gene mutation identified in people with distal myopathy 2 changes a single protein building block (amino acid) in the matrin 3 protein. The effect of this mutation on the function of the protein is unknown, although one study suggests that the mutation may change the location of the protein in the nucleus. Researchers are working to determine how this gene mutation leads to the signs and symptoms of distal myopathy 2.
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Is distal myopathy 2 inherited ?
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Distal myopathy 2 is inherited in an autosomal dominant pattern, which means one copy of the altered MATR3 gene in each cell is sufficient to cause the disorder.
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What are the treatments for distal myopathy 2 ?
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These resources address the diagnosis or management of distal myopathy 2: - Genetic Testing Registry: Myopathy, distal, 2 - MedlinePlus Encyclopedia: Muscular Dystrophy - National Institute of Neurological Disorders and Stroke: Muscular Dystrophy: Hope Through Research 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) succinate-CoA ligase deficiency ?
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Succinate-CoA ligase deficiency is an inherited disorder that affects the early development of the brain and other body systems. One of the earliest signs of the disorder is very weak muscle tone (severe hypotonia), which appears in the first few months of life. Severe hypotonia delays the development of motor skills such as holding up the head and rolling over. Many affected children also have muscle weakness and reduced muscle mass, which prevents them from standing and walking independently. Additional features of succinate-CoA ligase deficiency can include progressive abnormal curvature of the spine (scoliosis or kyphosis), uncontrolled movements (dystonia), severe hearing loss, and seizures beginning in childhood. In most affected children, a substance called methylmalonic acid builds up abnormally in the body and is excreted in urine (methylmalonic aciduria). Most children with succinate-CoA ligase deficiency also experience a failure to thrive, which means that they gain weight and grow more slowly than expected. Succinate-CoA ligase deficiency causes breathing difficulties that often lead to recurrent infections of the respiratory tract. These infections can be life-threatening, and most people with succinate-CoA ligase deficiency live only into childhood or adolescence. A few individuals with succinate-CoA ligase deficiency have had an even more severe form of the disorder known as fatal infantile lactic acidosis. Affected infants develop a toxic buildup of lactic acid in the body (lactic acidosis) in the first day of life, which leads to muscle weakness and breathing difficulties. Children with fatal infantile lactic acidosis usually live only a few days after birth.
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How many people are affected by succinate-CoA ligase deficiency ?
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Although the exact prevalence of succinate-CoA ligase deficiency is unknown, it appears to be very rare. This condition occurs more frequently among people from the Faroe Islands in the North Atlantic Ocean.
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What are the genetic changes related to succinate-CoA ligase deficiency ?
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Succinate-CoA ligase deficiency results from mutations in the SUCLA2 or SUCLG1 gene. SUCLG1 gene mutations can cause fatal infantile lactic acidosis, while mutations in either gene can cause the somewhat less severe form of the condition. The SUCLA2 and SUCLG1 genes each provide instructions for making one part (subunit) of an enzyme called succinate-CoA ligase. This enzyme plays a critical role in mitochondria, which are structures within cells that convert the energy from food into a form that cells can use. Mitochondria each contain a small amount of DNA, known as mitochondrial DNA or mtDNA, which is essential for the normal function of these structures. Succinate-CoA ligase is involved in producing and maintaining the building blocks of mitochondrial DNA. Mutations in either the SUCLA2 or SUCLG1 gene disrupt the normal function of succinate-CoA ligase. A shortage (deficiency) of this enzyme leads to problems with the production and maintenance of mitochondrial DNA. A reduction in the amount of mitochondrial DNA (known as mitochondrial DNA depletion) impairs mitochondrial function in many of the body's cells and tissues. These problems lead to hypotonia, muscle weakness, and the other characteristic features of succinate-CoA ligase deficiency.
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Is succinate-CoA ligase deficiency 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 succinate-CoA ligase deficiency ?
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These resources address the diagnosis or management of succinate-CoA ligase deficiency: - Gene Review: Gene Review: SUCLA2-Related Mitochondrial DNA Depletion Syndrome, Encephalomyopathic Form, with Mild Methylmalonic Aciduria - Genetic Testing Registry: Mitochondrial DNA depletion syndrome 5 (encephalomyopathic with or without methylmalonic aciduria) - Genetic Testing Registry: Mitochondrial DNA depletion syndrome 9 (encephalomyopathic with methylmalonic aciduria) - MedlinePlus Encyclopedia: Hypotonia - MedlinePlus Encyclopedia: Lactic Acidosis 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) Coffin-Siris syndrome ?
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Coffin-Siris syndrome is a condition that affects several body systems. Although there are many variable signs and symptoms, hallmarks of this condition include developmental disability, abnormalities of the fifth (pinky) fingers or toes, and characteristic facial features. Most affected individuals have mild to severe intellectual disability or delayed development of speech and motor skills such as sitting and walking. Another feature of Coffin-Siris syndrome is underdevelopment (hypoplasia) of the tips of the fingers or toes, or hypoplasia or absence of the nails. These abnormalities are most common on the fifth fingers or toes. In addition, most affected individuals have facial features described as coarse. These typically include a wide nose with a flat nasal bridge, a wide mouth with thick lips, and thick eyebrows and eyelashes. Affected individuals can have excess hair on other parts of the face and body (hirsutism), but scalp hair is often sparse. There is a range of facial features seen in people with Coffin-Siris syndrome, and not all affected individuals have the typical features. In addition, people with this condition may have an abnormally small head (microcephaly). Additionally, some infants and children with Coffin-Siris syndrome have frequent respiratory infections, difficulty feeding, and an inability to gain weight at the expected rate (failure to thrive). Other signs and symptoms that may occur in people with this condition include short stature, low muscle tone (hypotonia), and abnormally loose (lax) joints. Abnormalities of the eyes, brain, heart, and kidneys may also be present.
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How many people are affected by Coffin-Siris syndrome ?
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Coffin-Siris syndrome is a rare condition that is diagnosed in females more frequently than in males. Approximately 140 cases have been reported in the medical literature.
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What are the genetic changes related to Coffin-Siris syndrome ?
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Coffin-Siris syndrome is caused by mutations in the ARID1A, ARID1B, SMARCA4, SMARCB1, or SMARCE1 gene. Each of these genes provides instructions for making one piece (subunit) of several different SWI/SNF protein complexes. SWI/SNF complexes regulate gene activity (expression) by a process known as chromatin remodeling. Chromatin is the network of DNA and protein that packages DNA into chromosomes. The structure of chromatin can be changed (remodeled) to alter how tightly regions of DNA are packaged. Chromatin remodeling is one way gene expression is regulated during development; when DNA is tightly packed, gene expression is often lower than when DNA is loosely packed. Through their ability to regulate gene activity, SWI/SNF complexes are involved in many processes, including repairing damaged DNA; copying (replicating) DNA; and controlling the growth, division, and maturation (differentiation) of cells. Although it is unclear what effect mutations in these genes have on SWI/SNF complexes, researchers suggest that the mutations result in abnormal chromatin remodeling. Disturbance of this process alters the activity of many genes and disrupts several cellular processes, which could explain the diverse signs and symptoms of Coffin-Siris syndrome.
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Is Coffin-Siris syndrome inherited ?
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Coffin-Siris syndrome appears to follow an autosomal dominant pattern of inheritance, which means one copy of the altered gene in each cell is sufficient to cause the disorder. However, the condition is not usually inherited from an affected parent, but occurs from new (de novo) mutations in the gene that likely occur during early embryonic development.
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What are the treatments for Coffin-Siris syndrome ?
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These resources address the diagnosis or management of Coffin-Siris syndrome: - Gene Review: Gene Review: Coffin-Siris Syndrome - Genetic Testing Registry: Coffin-Siris 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) hyperprolinemia ?
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Hyperprolinemia is an excess of a particular protein building block (amino acid), called proline, in the blood. This condition generally occurs when proline is not broken down properly by the body. There are two inherited forms of hyperprolinemia, called type I and type II. People with hyperprolinemia type I often do not show any symptoms, although they have proline levels in their blood between 3 and 10 times the normal level. Some individuals with hyperprolinemia type I exhibit seizures, intellectual disability, or other neurological or psychiatric problems. Hyperprolinemia type II results in proline levels in the blood between 10 and 15 times higher than normal, and high levels of a related compound called pyrroline-5-carboxylate. This form of the disorder has signs and symptoms that vary in severity, and is more likely than type I to involve seizures or intellectual disability. Hyperprolinemia can also occur with other conditions, such as malnutrition or liver disease. In particular, individuals with conditions that cause elevated levels of lactic acid in the blood (lactic acidemia) may have hyperprolinemia as well, because lactic acid inhibits the breakdown of proline.
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How many people are affected by hyperprolinemia ?
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It is difficult to determine the prevalence of hyperprolinemia type I because most people with the condition do not have any symptoms. Hyperprolinemia type II is a rare condition; its prevalence is also unknown.
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What are the genetic changes related to hyperprolinemia ?
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Mutations in the ALDH4A1 and PRODH genes cause hyperprolinemia. Inherited hyperprolinemia is caused by deficiencies in the enzymes that break down (degrade) proline. Hyperprolinemia type I is caused by a mutation in the PRODH gene, which provides instructions for producing the enzyme proline oxidase. This enzyme begins the process of degrading proline by starting the reaction that converts it to pyrroline-5-carboxylate. Hyperprolinemia type II is caused by a mutation in the ALDH4A1 gene, which provides instructions for producing the enzyme pyrroline-5-carboxylate dehydrogenase. This enzyme helps to break down the pyrroline-5-carboxylate produced in the previous reaction, converting it to the amino acid glutamate. The conversion between proline and glutamate, and the reverse reaction controlled by different enzymes, are important in maintaining a supply of the amino acids needed for protein production, and for energy transfer within the cell. A deficiency of either proline oxidase or pyrroline-5-carboxylate dehydrogenase results in a buildup of proline in the body. A deficiency of the latter enzyme leads to higher levels of proline and a buildup of the intermediate breakdown product pyrroline-5-carboxylate, causing the signs and symptoms of hyperprolinemia type II.
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Is hyperprolinemia 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 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. In about one-third of cases, individuals carrying one copy of an altered PRODH gene have moderately elevated levels of proline in their blood, but these levels do not cause any health problems. Individuals with one altered ALDH4A1 gene have normal levels of proline in their blood.
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What are the treatments for hyperprolinemia ?
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These resources address the diagnosis or management of hyperprolinemia: - Baby's First Test - Genetic Testing Registry: Deficiency of pyrroline-5-carboxylate reductase - Genetic Testing Registry: Proline dehydrogenase deficiency 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) succinyl-CoA:3-ketoacid CoA transferase deficiency ?
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Succinyl-CoA:3-ketoacid CoA transferase (SCOT) deficiency is an inherited disorder that impairs the body's ability to break down ketones, which are molecules produced in the liver during the breakdown of fats. The signs and symptoms of SCOT deficiency typically appear within the first few years of life. Affected individuals experience episodes of extreme tiredness (lethargy), appetite loss, vomiting, rapid breathing, and, occasionally, seizures. These episodes, which are called ketoacidotic attacks, sometimes lead to coma. About half of affected individuals have a ketoacidotic attack within the first 4 days of life. Affected individuals have no symptoms of the disorder between ketoacidotic attacks. People with SCOT deficiency usually have a permanently elevated level of ketones in their blood (persistent ketosis). If the level of ketones gets too high, which can be brought on by infections, fevers, or periods without food (fasting), a ketoacidotic attack can occur. The frequency of ketoacidotic attacks varies among affected individuals.
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How many people are affected by succinyl-CoA:3-ketoacid CoA transferase deficiency ?
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The prevalence of SCOT deficiency is unknown. More than 20 cases of this condition have been reported in the scientific literature.
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What are the genetic changes related to succinyl-CoA:3-ketoacid CoA transferase deficiency ?
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Mutations in the OXCT1 gene cause SCOT deficiency. The OXCT1 gene provides instructions for making an enzyme called succinyl-CoA:3-ketoacid CoA transferase (SCOT). The SCOT enzyme is made in the energy-producing centers of cells (mitochondria). The enzyme plays a role in the breakdown of ketones, which are an important source of energy during fasting or when energy demands are increased, such as during illness or when exercising. OXCT1 gene mutations result in the production of a SCOT enzyme with little or no function. A reduction in the amount of functional enzyme leads to an inability to break down ketones, resulting in decreased energy production and an elevated level of ketones in the blood. If these signs become severe, a ketoacidotic attack can occur. Individuals with mutations that create an enzyme with partial function are still prone to ketoacidotic attacks, but are less likely to have persistent ketosis.
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Is succinyl-CoA:3-ketoacid CoA transferase deficiency 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 succinyl-CoA:3-ketoacid CoA transferase deficiency ?
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These resources address the diagnosis or management of succinyl-CoA:3-ketoacid CoA transferase deficiency: - Genetic Testing Registry: Succinyl-CoA acetoacetate transferase deficiency - MedlinePlus Encyclopedia: Ketones--Urine - MedlinePlus Encyclopedia: Serum Ketones Test 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) episodic ataxia ?
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Episodic ataxia is a group of related conditions that affect the nervous system and cause problems with movement. People with episodic ataxia have recurrent episodes of poor coordination and balance (ataxia). During these episodes, many people also experience dizziness (vertigo), nausea and vomiting, migraine headaches, blurred or double vision, slurred speech, and ringing in the ears (tinnitus). Seizures, muscle weakness, and paralysis affecting one side of the body (hemiplegia) may also occur during attacks. Additionally, some affected individuals have a muscle abnormality called myokymia during or between episodes. This abnormality can cause muscle cramping, stiffness, and continuous, fine muscle twitching that appears as rippling under the skin. Episodes of ataxia and other symptoms can begin anytime from early childhood to adulthood. They can be triggered by environmental factors such as emotional stress, caffeine, alcohol, certain medications, physical activity, and illness. The frequency of attacks ranges from several per day to one or two per year. Between episodes, some affected individuals continue to experience ataxia, which may worsen over time, as well as involuntary eye movements called nystagmus. Researchers have identified at least seven types of episodic ataxia, designated type 1 through type 7. The types are distinguished by their pattern of signs and symptoms, age of onset, length of attacks, and, when known, genetic cause.
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How many people are affected by episodic ataxia ?
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Episodic ataxia is uncommon, affecting less than 1 in 100,000 people. Only types 1 and 2 have been identified in more than one family, and type 2 is by far the most common form of the condition.
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