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Disease List:

3 6 A B C D E F G H I J K L M N O P R S T U V W Z

Cohen Syndrome

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What is Cohen Syndrome?

Cohen Syndrome is an autosomal recessive disorder that affects many parts of the body. Signs and symptoms begin in infancy and include developmental delay, small head size, a distinctive facial appearance, and hypotonia (low muscle tone).  Affected children have intellectual disability, vision problems, overly mobile joints, obesity, short stature, narrow hands and feet, and neutropenia (low level of white blood cells). Currently there is no cure for Cohen Syndrome and treatment is based on symptoms.

What causes Cohen Syndrome?

Cohen Syndrome is caused by a gene change, or mutation, in both copies of the VPS13B gene pair (also known as COH1).  These mutations cause the genes to not work properly or not work at all. When both copies of the VPS13B gene pair do not work correctly, it leads to the symptoms described above.  

Combined Malonic and Methylmalonic Aciduria

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What is Combined Malonic and Methylmalonic Aciduria?

Combined Malonic and Methylmalonic Aciduria is an autosomal recessive disorder that causes high levels of malonic acid and methylmalonic acid in the body and urine.  Signs and symptoms can begin in childhood or adulthood.  In those with childhood-onset disease, symptoms may include organ damage due to acidosis, involuntary muscles tension, weak muscle tone, developmental delays, poor growth and weight gain, small head size, low blood sugar, or even coma.  For those with delayed adult-onset disease, symptoms usually include seizures, memory loss, cognitive decline, or psychiatric disease.

What causes Combined Malonic and Methylmalonic Aciduria?

Combined Malonic and Methylmalonic Aciduria is caused by a change, or mutation, in both copies of the ACSF3 gene pair.  These mutations cause the ACSF3 genes to not work properly or not work at all.  When both copies of this gene do not work correctly, it leads to the symptoms described above.

Combined Oxidative Phosphorylation Deficiency 1

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What is Combined Oxidative Phosphorylation Deficiency 1?

Combined Oxidative Phosphorylation Deficiency 1 is a severe autosomal recessive disorder that begins before birth and affects many parts of the body including the brain, nervous system, heart, and liver. Symptoms in affected infants include growth delay, small head size, brain abnormalities, tight muscles, decreased movements, seizures, developmental delay, and poor muscle tone. Affected infants also develop cardiomyopathy (an enlarged heart that does not pump properly), and liver disease. Symptoms progressively worsen and death often occurs in infancy or in the first few years of life.  Currently there is no cure for this condition.

What causes Combined Oxidative Phosphorylation Deficiency 1?

Combined Oxidative Phosphorylation Deficiency 1 is caused by a change, or mutation, in both copies of the GFM1 gene pair.  These mutations cause the genes to not work properly or not work at all. When both copies of the GFM1 gene pair do not work correctly, it leads to the symptoms described above.

Combined Oxidative Phosphorylation Deficiency 3

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What is Combined Oxidative Phosphorylation Deficiency 3?

Combined Oxidative Phosphorylation Deficiency 3 is an autosomal recessive disorder that affects the mitochondria, the energy-producing parts of the cells.  This condition affects many parts of the body including the brain, nervous system, heart, and liver.  Signs and symptoms usually begin before or at birth.  Infants typically have a slower than average growth rate, brain abnormalities, tight muscles (spasticity), abnormal movements, seizures, developmental delay, muscle weakness, and poor muscle tone.  Many infants also have episodes of metabolic acidosis in which toxic substances build up in the blood and cause lack of energy, vomiting, breathing problems, seizures, and sometimes coma or death.  Some infants also develop an enlarged heart (cardiomyopathy) and enlarged liver.  Children with the severe form of this condition often die in infancy or early childhood.  Some children with Combined Oxidative Phosphorylation Deficiency 3 have a milder form of the condition with symptoms that show up later that may include learning disabilities or intellectual disability, vision loss, muscle weakness, and a movement disorder.  Currently there is no cure or specific treatment for this condition.

What causes Combined Oxidative Phosphorylation Deficiency 3?

Combined Oxidative Phosphorylation Deficiency 3 is caused by a gene change, or mutation, in both copies of the TSFM gene pair.  These mutations cause the genes to not work properly or not work at all.  When both copies of this gene do not work properly, it leads to the symptoms described above.

Combined Pituitary Hormone Deficiency-2

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What is Combined Pituitary Hormone Deficiency-2?

Combined Pituitary Hormone Deficiency-2 is an autosomal recessive disorder that causes short stature and other health and developmental problems.  These symptoms are caused by lack of pituitary hormones in the body.  Pituitary hormones are made in the brain by the pituitary gland.  Affected infants have low blood sugar (hypoglycemia), seizures (due to hypoglycemia), and growth delay.  Hypothyroidism and cortisol deficiency can also occur.  Without treatment affected individuals have short stature and may have delayed or absent puberty and infertility (inability to have biological children).  Treatment includes lifelong pituitary hormone replacement therapy.  With treatment, affected individuals can lead healthy lives. 

What causes Combined Pituitary Hormone Deficiency-2?

Combined Pituitary Hormone Deficiency-2 is caused by a change, or mutation, in both copies of the PROP1 gene pair.  These mutations cause the genes to not work properly or not work at all.  The PROP1 genes are important in the development of the pituitary gland. When both copies of this gene do not work correctly, the pituitary gland is unable to make the hormones that are important for growth and onset of puberty, leading to the symptoms described above.

Congenital Adrenal Hyperplasia, 17-Alpha-Hydroxylase Deficiency

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What is Congenital Adrenal Hyperplasia, 17-Alpha-Hydroxylase Deficiency?

Congenital Adrenal Hyperplasia, 17-Alpha-Hydroxylase Deficiency is an autosomal recessive disorder that causes decreased production of sex hormones in the body.  Affected males are born with external genitals that do not have the typical appearance of male or female (ambiguous genitalia) and without treatment they will not go through normal puberty. Affected females are born with normal external genitals but without treatment, they will not go through normal puberty or develop secondary sexual characteristics.  Both males and females with this disorder have hypertension (high blood pressure) and low potassium levels. Treatment includes hormone replacement therapies. 

What causes Congenital Adrenal Hyperplasia, 17-Alpha-Hydroxylase Deficiency?

Congenital Adrenal Hyperplasia, 17-Alpha-Hydroxylase Deficiency is caused by a change, or mutation, in both copies of the CYP17A1 gene pair.  These mutations cause the genes to not work properly or not work at all.  The function of the CYP17A1 genes is to help make sex hormones and other hormones.  When both copies of this gene do not work correctly, it leads to the symptoms described above. 

Congenital Amegakaryocytic Thrombocytopenia

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What is Congenital Amegakaryocytic Thrombocytopenia?

Congenital Amegakaryocytic Thrombocytopenia is a rare autosomal recessive disorder that leads to a reduced number of certain blood cells (megakaryocytes) that make platelets, which are needed for blood clotting.  This can progress to bone marrow failure over time. Symptoms are usually seen within the first week to nine months of life and include bleeding in the lung, intestines, brain, and skin. Some children also have delayed development and or heart defects. Treatment includes repeated blood transfusions or stem cell transplant.  If left untreated, about a third of patients with Congenital Amegakaryocytic Thrombocytopenia die of bleeding complications or bone marrow failure.

What causes Congenital Amegakaryocytic Thrombocytopenia?

Congenital Amegakaryocytic Thrombocytopenia is caused by a gene change, or mutation, in both copies of the MPL gene.  These mutations cause the genes to not work properly or not work at all.  When both copies of the MPL gene do not work correctly, it causes the symptoms described above.

Congenital Disorder of Glycosylation, Type 1A, PMM2-Related

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What is Congenital Disorder of Glycosylation, Type 1A, PMM2-Related?

Congenital Disorder of Glycosylation, Type 1A, PMM2-Related is an autosomal recessive disorder that affects many parts of the body.  Signs and symptoms usually begin in infancy and include weak muscle tone, inverted nipples, abnormal distribution of fat, eyes that do not look in the same direction (strabismus), distinct facial features, developmental delay, and a failure to grow or gain weight.  Children with Congenital Disorder of Glycosylation, Type 1A, PMM2-Related may also have an underdeveloped area of brain, called the cerebellum, which controls and coordinates body movement.  Children with this disorder may also have elevated liver function tests, seizures, fluid around the heart, and blood clotting disorders.  The symptoms of this condition can be life-threatening and about 20% of affected infants die within the first year of life.  Affected individuals may develop moderate intellectual disability in childhood and some are unable to walk independently; some may also experience stroke-like episodes.  Teenagers and adults with Congenital Disorder of Glycosylation, Type 1A, PMM2-Related may have reduced sensation and weakness in their arms and legs, an abnormal curvature of the spine, impaired muscle coordination, and joint deformities.  Some affected individuals experience significant vision loss.  Females with Congenital Disorder of Glycosylation, Type 1A, PMM2-Related typically do not go through puberty. Currently there is no cure for this disorder and treatment is based on symptoms.

What causes Congenital Disorder of Glycosylation, Type 1A, PMM2-Related?

Congenital Disorder of Glycosylation, Type 1A, PMM2-Related is caused by a change, or mutation, in both copies of the PMM2 gene pair.  These mutations cause the genes to not work properly or not work at all.  When both copies of this gene do not work correctly, it leads to the symptoms described above.

Congenital Disorder of Glycosylation, Type 1B

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What is Congenital Disorder of Glycosylation, Type 1B?

Congenital Disorder of Glycosylation, Type 1B is an autosomal recessive disorder that causes problems with the growth and function of the body.  Symptoms begin in infancy and include failure to gain weight and slower than average growth (failure to thrive).  Affected children can have poor muscle tone (hypotonia), digestive problems, malnutrition, liver disease, increased number of infections, low blood sugar, and problems forming blood clots. Treatment can be successful in reversing symptoms.  Lack of treatment may result in death.  Intellectual disability and neurologic problems are not present in Congenital Disorder of Glycosylation, Type 1B in contrast to other types of Congenital Disorders of Glycosylation. 

What causes Congenital Disorder of Glycosylation, Type 1B?

Congenital Disorder of Glycosylation, Type 1B is caused by a gene change, or mutation, in both copies of the MPI gene. These mutations cause the genes to not work properly or not work at all. The function of the MPI genes is to help process fats and proteins from the diet so that they can be used in the body.  When both copies of this gene do not work correctly, it leads to the symptoms described above. 

Congenital Disorder of Glycosylation, Type 1C

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What is Congenital Disorder of Glycosylation, Type 1C?

Congenital Disorder of Glycosylation, Type 1C is an autosomal recessive disorder that causes problems with the growth and function of the body.  Symptoms begin in infancy and include failure to gain weight and slower than average growth (failure to thrive).  Affected children can have neurologic problems including poor muscle tone (hypotonia), developmental delay, problems with balance and movement (ataxia), seizures, and in some cases, stroke-like episodes. Vision problems, including strabismus (lazy eye) and a vision loss condition called retinitis pigmentosa, can also occur in Congenital Disorder of Glycosylation, Type 1C.  Affected females often have low levels of sex hormones and may not go through puberty without hormone replacement therapy.

What causes Congenital Disorder of Glycosylation, Type 1C?

Congenital Disorder of Glycosylation, Type 1C is caused by a gene change, or mutation, in both copies of the ALG6 gene. These mutations cause the genes to not work properly or not work at all. The function of the ALG6 genes is to help process fats and proteins from the diet so that they can be used in the body.  When both copies of this gene do not work correctly, it leads to the symptoms described above. 

Congenital Finnish Nephrosis

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What is Congenital Finnish Nephrosis?

Congenital Finnish Nephrosis, also known as Nephrotic Syndrome Type 1, is an autosomal recessive disorder that affects the kidneys. Symptoms often begin before birth and may include a large placenta and premature birth. Affected babies have swelling of the body (edema). The kidneys become more damaged over time which leads to too much protein being lost in the urine. In most cases the kidney disease progresses to complete renal failure within the first 10 years of life. Without a kidney transplant affected individuals often die in childhood.

What causes Congenital Finnish Nephrosis?

Congenital Finnish Nephrosis is caused by a gene change, or mutation in both copies of the NPHS1 gene pair.  These mutations cause the genes to not work properly or not work at all.  When both copies of the NPHS1 gene do not work correctly, it leads to the kidney damage and symptoms described above.

Congenital Hyperinsulinism, KCNJ11-Related

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What is Congenital Hyperinsulinism, KCNJ11-Related?

Congenital Hyperinsulinism, KCNJ11-Related (also called Hyperinsulinemic Hypoglycemia) is an autosomal recessive disorder that causes abnormally high levels of insulin, the hormone that controls blood sugar. This leads to episodes of low blood sugar (hypoglycemia), usually starting the first few days or months of life. Low blood sugar causes lack of energy, irritability, and poor feeding. If left untreated it may lead to seizures and brain damage. Symptoms also include poor muscle tone and breathing problems. Treatment with special diet and medications may help reduce the symptoms, but some children may need surgery to remove all or part of the pancreas. If not treated, this condition can cause intellectual disability.

What causes Congenital Hyperinsulinism, KCNJ11-Related?

Congenital Hyperinsulinism, KCNJ11-Related is caused by a gene change, or mutation, in both copies of the KCNJ11 gene pair. These mutations cause the KCNJ11 genes to not work properly or not work at all. When both copies of this gene do not work correctly, it leads to the symptoms described above.

Less commonly, mutations in the same gene cause a different disorder, either Permanent Neonatal Diabetes Mellitus or Transient Neonatal Diabetes Mellitus. Babies with these conditions have low birth weight and high blood sugar (hyperglycemia), dehydration and growth failure within the first 6 months of life. Transient Neonatal Diabetes Mellitus typically resolves before age 2 but often returns again in the teens or early adulthood. Permanent Neonatal Diabetes Mellitus needs lifelong treatment. Some children with Permanent Neonatal Diabetes Mellitus also have developmental delay, seizures, or learning problems. Neonatal Diabetes Mellitus is usually inherited in and autosomal dominant manner from a parent who is affected with the disorder. It is sometimes, but not always, possible to determine whether a specific mutation in the KCNJ11 gene will cause Congenital Hyperinsulinism, KCNJ11-Related or Neonatal Diabetes Mellitus. 

Congenital Insensitivity to Pain with Anhidrosis (CIPA)

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What is Congenital Insensitivity to Pain with Anhidrosis (CIPA)?

Congenital Insensitivity to Pain with Anhidrosis (CIPA) is an autosomal recessive disorder that affects the nervous system. People with this disorder cannot feel pain or temperature changes, have reduced or absent sweating (anhidrosis), and most have some degree of intellectual disability.  Signs and symptoms of CIPA usually begin at birth or shortly after and, because of repeated injuries and burns that cannot be felt, the condition is life-threatening. High fevers are common and can lead to seizures if not treated. Other symptoms may include slow healing of wounds and broken bones, thickened skin, and patchy hair loss.  About half of all people with this condition have emotional and behavioral problems that may include anxiety and severe attention deficit hyperactivity disorder (ADHD).  Currently there is no cure for this condition, but with supportive treatment people with CIPA can live into adulthood.

What causes Congenital Insensitivity to Pain with Anhidrosis (CIPA)?

Congenital Insensitivity to Pain with Anhidrosis is caused by a gene change, or mutation, in both copies of the NTRK1 gene pair.  These mutations cause the genes to not work properly or not work at all.  When both copies of this gene do not work correctly, it leads to the symptoms described above.

Congenital Myasthenic Syndrome, CHRNE-Related

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What is Congenital Myasthenic Syndrome, CHRNE-Related?

Congenital Myasthenic Syndrome, CHRNE-Related is an inherited disorder that affects the muscles and is usually autosomal recessive but, in some late-onset cases, is autosomal dominant.  Symptoms of muscle weakness (myasthenia) can begin after birth but may begin later in life.  Affected infants and children often have feeding and swallowing problems, developmental delay, and at times may have breathing problems.  Muscle weakness can worsen with exercise.  Speech problems may occur due to facial muscle weakness.  The weakness remains stable and does not worsen with age.  The degree of muscle weakness varies among individuals affected with Congenital Myasthenic Syndrome, CHRNE-Related.  Some individuals have later onset of symptoms that may include weakness of the neck, wrist, and fingers along with progressive breathing problems. 

What causes Congenital Myasthenic Syndrome, CHRNE-Related?

Most cases of Congenital Myasthenic Syndrome, CHRNE-Related are caused by a change, or mutation, in both copies of the CHRNE gene pair. These mutations cause the genes to not work properly or not work at all.  When both copies of the CHRNE gene do not work correctly, the signals from the nerves to the muscles are disrupted, causing problems with movement of skeletal muscles, muscle weakness, and delayed development of motor skills.

Some cases of late-onset Congenital Myasthenic Syndrome, CHRNE-Related are inherited in an autosomal dominant manner.  This means that a person who has a mutation in just one copy of the CHRNE gene will have symptoms of the late-onset form of this condition. 

Congenital Myasthenic Syndrome, RAPSN-Related

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What is Congenital Myasthenic Syndrome, RAPSN-Related?

Congenital Myasthenic Syndrome, RAPSN-Related is an autosomal recessive disorder that causes muscle weakness that becomes worse during physical exercise. The first symptoms of this disorder usually appear shortly after birth. Occasionally, symptoms may not appear until late childhood, adolescence, or adulthood. The symptoms vary from person to person but the muscles of the face are almost always affected.  This causes problems with holding up the head, opening and closing the eyes, chewing, and swallowing. Most children with this disorder have problems eating, delayed crawling and walking, and poor coordination.  Some children with this condition have more severe muscle weakness and cannot walk.  Breathing problems, especially during illness, happen in some children.   

What causes Congenital Myasthenic Syndrome, RAPSN-Related?

Congenital Myasthenic Syndrome, RAPSN-Related is caused by a gene change, or mutation, in both copies of the RAPSN gene pair.  These mutations cause the genes to not work properly or not work at all.  When both copies of this gene do not work correctly, it leads to the symptoms described above.

Congenital Neutropenia, HAX1-Related

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What is Congenital Neutropenia, HAX1-Related?

Congenital Neutropenia, HAX1-Related is an autosomal recessive disorder that causes low levels of immune cells called neutrophils (a type of white blood cell).  This causes problems with immune system function.  Affected individuals have symptoms beginning in infancy with frequent bacterial infections.  Over time, there is an increased risk of developing blood cancers. In addition, some affected children have intellectual disability, developmental delay, and seizures.  Early death due to infection may occur in some children.

What causes Congenital Neutropenia, HAX1-Related?

Congenital Neutropenia, HAX1-Related is caused by a gene change, or mutation, in both copies of the HAX1 gene pair. These mutations cause the genes to not work properly or not work at all. When both copies of the HAX1 gene do not work correctly, it causes early death of neutrophils, leading to low levels in the bloodstream. This leads to the symptoms described above. 

Congenital Neutropenia, VPS45-Related

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What is Congenital Neutropenia, VPS45-Related?

Congenital Neutropenia, VPS45-Related is an autosomal recessive disorder that causes low levels of immune cells called neutrophils (a type of white blood cell). This causes problems with immune system function.  Affected individuals have symptoms beginning in infancy with frequent bacterial infections.  Over time, there is an increased risk of developing blood cancers. In addition, some affected children have developmental delay.  Early death due to infection may occur in some children.  

What causes Congenital Neutropenia, VPS45-Related?

Congenital Neutropenia, VPS45-Related is caused by a gene change, or mutation, in both copies of the VPS45 gene pair.  These mutations cause the genes to not work properly or not work at all. When both copies of the VPS45 gene do not work correctly, the neutrophils that are produced either do not function properly or die off prematurely, leading to low levels in the bloodstream.  This causes the symptoms described above. 

Corneal Dystrophy and Perceptive Deafness

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What is Corneal Dystrophy and Perceptive Deafness?

Corneal Dystrophy and Perceptive Deafness is an autosomal recessive disorder that causes eye abnormalities and vision and hearing loss. Symptoms usually begin in later childhood or adulthood. The eye problems involve worsening buildup of substances in the cornea (outer layer) of the eye, leading to vision loss.  Hearing loss usually begins in childhood and worsens with age.  Corneal Dystrophy and Perceptive Deafness is also called Harboyan Syndrome.

A different form of this condition, called Corneal Dystrophy, Endothelial 2 is caused by changes in the same gene and has symptoms that are present at birth.  Corneal Dystrophy, Endothelial 2 causes thickening and clouding of the cornea leading to blurred vision and nystagmus (rapid, jittery eye movements) and sometimes causes hearing loss. Currently there is no cure for these conditions and treatment is based on symptoms.

What causes Corneal Dystrophy and Perceptive Deafness?

Both Corneal Dystrophy and Perceptive Deafness and Corneal Dystrophy, Endothelial 2 are caused by a gene change, or mutation, in both copies of the SLC4A11 gene pair.  These mutations cause the genes to not work properly or not work at all. When both copies of the gene do not work correctly, it leads to either Corneal Dystrophy and Perceptive Deafness or Corneal Dystrophy, Endothelial 2 . 

Corticosterone Methyloxidase Deficiency

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What is Corticosterone Methyloxidase Deficiency?

Corticosterone Methyloxidase Deficiency, also called Aldosterone Synthase Deficiency, is an autosomal recessive disorder that causes too much sodium to be excreted in the urine. This leads to decreased levels of sodium and increased levels of potassium in the blood. Symptoms begin shortly after birth and include poor feeding, nausea, vomiting, fatigue, low blood pressure, muscle weakness, and dehydration. Severe forms of this disorder may lead to metabolic acidosis, where the blood becomes too acidic. Metabolic acidosis can cause seizures and coma, which may be life-threatening. This condition is treated with hormone replacement therapy. Most people with this condition who survive the newborn period have mild or no symptoms in adulthood. 

Very rarely a specific mutation in the same gene causes a separate disorder called Familial Hyperaldosteronism which is inherited in an autosomal dominant manner.  In this disorder, the body makes too much aldosterone, a hormone made by the adrenal gland, which causes severe high blood pressure (hypertension).  If not treated, there is an increased risk for stroke, heart disease, and kidney failure.  It is usually possible to tell whether a specific gene mutation will cause Corticosterone Methyloxidase Deficiency or Familial Hyperaldosteronism.

What causes Corticosterone Methyloxidase Deficiency?

Corticosterone Methyloxidase Deficiency is caused by a gene change, or mutation, in both copies of the CYP11B2 gene pair.  These mutations cause the genes to not work properly or not work at all.  Normal function of the CYP11B2 gene pair is needed to make a hormone called aldosterone which regulates salt balance in the body. When both copies of the CYP11B2 gene do not work correctly, it leads to the symptoms described above.

Familial Hyperaldosteronism (FH) is autosomal dominant.  A person with an FH-causing mutation in one copy of the CYP11B2 gene pair is affected with the disorder.

Costeff Syndrome (3-Methylglutaconic Aciduria, Type 3)

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What is Costeff Syndrome (3-Methylglutaconic Aciduria, Type 3)?

Costeff Syndrome (also known as 3-Methylglutaconic Aciduria, Type 3) is an autosomal recessive disorder that causes vision loss, jerky movements called chorea, muscle stiffness and, in some people, mild intellectual disability. Vision loss caused by breakdown, or atrophy, of the optic nerve often starts in childhood and worsens over time. Problems with muscle control and movement start later in childhood and worsen over time, sometimes leading to wheelchair use. High levels of 3-methylglutaconic acid are found in the urine of people with this condition. This does not cause the health problems seen in Costeff Syndrome but can help diagnose the condition. Currently there is no cure for this disorder and treatment is based on symptoms.

What causes Costeff Syndrome?

Costeff Syndrome is caused by a gene change, or mutation, in both copies of the OPA3 gene pair. These mutations cause the genes to not work properly or not work at all. When both copies of the OPA3 gene do not work correctly, it leads to the symptoms described above. 

Very rarely, a mutation in the same gene causes a related disorder called Autosomal Dominant Optic Atrophy and Cataract. People with this disorder have progressive vision loss in both eyes due to atrophy of the optic nerves and clouding of the lens of the eye. The vision loss can start in childhood or early adulthood. 

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