Comprehensive
screening options

Comprehensive
screening options

Comprehensive
screening options

Comprehensive
screening options

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

3-Beta-Hydroxysteroid Dehydrogenase Type II Deficiency

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What is 3-Beta-Hydroxysteroid Dehydrogenase Type II Deficiency?

3-Beta-Hydroxysteroid Dehydrogenase Type II Deficiency is an autosomal recessive condition.  It is one of a group of inherited disorders called Congenital Adrenal Hyperplasia that affect the hormones made by the ovaries, testes, and adrenal glands.  People with 3-Beta-Hydroxysteroid Dehydrogenase Type II Deficiency do not make enough of certain hormones needed by the body. There are three forms of this condition: salt-wasting, non-salt-wasting, and non-classical.  Babies with the salt-wasting form have symptoms that start shortly after birth and include poor feeding, vomiting, and dehydration which can lead to death if not treated. People with the non-salt-wasting and non-classical forms do not have these symptoms.  All three forms result in decreased amounts of sex hormones. This leads to abnormal development of the genitals in males which sometimes results in external genitals that look female instead of male (ambiguous genitalia).  Without treatment, both males and females with this condition do not go through normal puberty and often cannot have their own children. Without treatment, high blood pressure and low potassium levels are also common.  People with the non-classical form of the condition have symptoms that are typically milder than the other two forms. Treatment includes hormone replacement therapies and sometimes other supplements or medications.

What causes 3-Beta-Hydroxysteroid Dehydrogenase Type II Deficiency?

3-Beta-Hydroxysteroid Dehydrogenase Type II Deficiency is caused by a gene change, or mutation, in both copies of the HSD3B2 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.

3-Hydroxy-3-Methylglutaryl-Coenzyme A Lyase Deficiency

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What is 3-Hydroxy-3-Methylglutaryl-Coenzyme A Lyase Deficiency?

3-Hydroxy-3-Methylglutaryl-Coenzyme A (HMG-CoA) Lyase Deficiency is an autosomal recessive condition.  It is one of a group of inherited disorders known as Organic Acid Disorders.  People with HMG-CoA Lyase Deficiency cannot break down leucine, one of the building blocks of protein, and cannot use body fat as energy.  Signs and symptoms often start in infancy or early childhood and include lack of energy, poor feeding, poor muscle tone, diarrhea, vomiting, low blood sugar (hypoglycemia), breathing problems, seizures, and coma, which, if left untreated, can lead to death.  Episodes of low blood sugar and metabolic acidosis, where toxic substances build up in the blood, can be triggered by going a long time without food (fasting), illness, or eating large amounts of protein.  If the condition is not treated, repeated episodes of metabolic acidosis can lead to an enlarged heart and liver, vision and hearing loss, and intellectual disability.  Symptoms vary from person to person and some people never show symptoms.  Treatment includes a medical diet low in protein and fat, other supplements and medications, and avoidance of fasting.  If treatment is started early, people with this condition can often live healthy lives.  However, even with careful treatment, some children still have repeated episodes of metabolic acidosis and low blood sugar.

What causes 3-Hydroxy-3-Methylglutaryl-Coenzyme A Lyase Deficiency?

HMG-CoA Lyase Deficiency is caused by a gene change, or mutation, in both copies of the HMGCL 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.

3-Methylcrotonyl-CoA Carboxylase 1 Deficiency

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What is 3-Methylcrotonyl-CoA Carboxylase 1 Deficiency?

3-Methylcrotonyl-CoA Carboxylase 1 Deficiency is an autosomal recessive condition.  It is one of a group of inherited disorders known as Organic Acid Disorders.  People with 3-Methylcrotonyl-CoA Carboxylase 1 Deficiency cannot break down a building block of protein called leucine.  When food containing leucine is eaten, harmful substances build up in the blood causing repeated episodes of metabolic acidosis.  These episodes may include vomiting, lack of energy, muscle weakness, sleep disturbances, breathing problems, low blood sugar (hypoglycemia), seizures, coma, and sometimes even death.  These episodes are often triggered by eating large amounts of protein, going a long time without food (fasting), or illness. If not treated, this condition can lead to developmental delays and intellectual disability, poor growth, muscle problems, and liver failure. Symptoms can range from mild to severe and often begin in infancy or childhood, although some people do not have symptoms until adulthood and others never show symptoms. Treatment for children with 3-Methylcrotonyl-CoA Carboxylase 1 Deficiency who show symptoms includes a medical low-protein diet and specific supplements. Treatment can prevent or lessen the symptoms in most people with this condition although some still have repeated episodes of metabolic acidosis even with careful treatment.   

What causes 3-Methylcrotonyl-CoA Carboxylase 1 Deficiency?

3-Methylcrotonyl-CoA Carboxylase 1 Deficiency is caused by a gene change, or mutation, in both copies of the MCCC1 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.

3-Methylcrotonyl-CoA Carboxylase 2 Deficiency

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What is 3-Methylcrotonyl-CoA Carboxylase 2 Deficiency?

3-Methylcrotonyl-CoA Carboxylase 2 Deficiency is an autosomal recessive condition.  It is one of a group of inherited disorders known as Organic Acid Disorders.  People with 3-Methylcrotonyl-CoA Carboxylase 2 Deficiency cannot break down a building block of protein called leucine.  When food containing leucine is eaten, harmful substances build up in the blood causing repeated episodes of metabolic acidosis.  These episodes may include vomiting, lack of energy, muscle weakness, sleep disturbances, breathing problems, low blood sugar (hypoglycemia), seizures, coma, and sometimes even death.  These episodes are often triggered by eating large amounts of protein, going a long time without food (fasting), or illness. If not treated, this condition can lead to developmental delays and intellectual disability, poor growth, muscle problems, and liver failure. Symptoms can range from mild to severe and often begin in infancy or childhood, although some people do not have symptoms until adulthood and others never show symptoms. Treatment for children with 3-Methylcrotonyl-CoA Carboxylase 2 Deficiency who show symptoms includes a medical low-protein diet and specific supplements. Treatment can prevent or lessen the symptoms in most people with this condition although some still have repeated episodes of metabolic acidosis even with careful treatment.   

What causes 3-Methylcrotonyl-CoA Carboxylase 2 Deficiency?

3-Methylcrotonyl-CoA Carboxylase 2 Deficiency is caused by a gene change, or mutation, in both copies of the MCCC2 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.

3-Phosphoglycerate Dehydrogenase Deficiency

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What is 3-Phosphoglycerate Dehydrogenase Deficiency?

3-Phosphoglycerate Dehydrogenase Deficiency is an autosomal recessive disorder that affects the brain and nervous system.  Signs and symptoms usually begin infancy and include small head size (microcephaly), developmental delays, growth delay, intellectual disability, and seizures.  The brain develops abnormally and over time there is loss of brain tissue.  Affected infants may not achieve developmental milestones such as speech or sitting up without assistance.  In rare cases symptoms do not begin until childhood or adulthood.  Currently there is no cure for this condition; however, amino acid therapy may reduce seizures and other symptoms if treatment is started early in life.   

What causes 3-Phosphoglycerate Dehydrogenase Deficiency?

3-Phosphoglycerate Dehydrogenase Deficiency is caused by a change, or mutation, in both copies of the PHGDH gene pair.  These mutations cause the genes to not work properly or not work at all.  Normal function of the PHGDH genes is important for development and function of the brain and spinal cord (central nervous system). When both copies of the PHGDH gene pair do not work correctly it leads to the symptoms described above. 

6-Pyruvoyl-Tetrahydropterin Synthase (PTPS) Deficiency

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What is 6-Pyruvoyl-Tetrahydropterin Synthase (PTPS) Deficiency?

6-Pyruvoyl-Tetrahydropterin Synthase (PTPS) Deficiency is an autosomal recessive disorder in which the body cannot break down a specific building block of protein called phenylalanine. Phenylalanine is in most protein found in the diet and, if it cannot be broken down, it builds up in the blood and causes damage to the brain and nervous system. If untreated, symptoms of PTPS Deficiency usually begin shortly after birth and include seizures, abnormal muscle tone, unusual movements, and intellectual disability. Early treatment with a special medical low-phenylalanine diet and other supplements can often prevent or lessen the severity of symptoms.  

What causes 6-Pyruvoyl-Tetrahydropterin Synthase (PTPS) Deficiency?

6-Pyruvoyl-Tetrahydropterin Synthase (PTPS) Deficiency is caused by a gene change, or mutation, in both copies of the PTS 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.

Abetalipoproteinemia

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What is Abetalipoproteinemia?

Abetalipoproteinemia is a rare autosomal recessive disorder that prevents the body from completely absorbing certain dietary fats and the essential vitamins A, D, E, and K. Signs and symptoms of Abetalipoproteinemia usually begin in infancy but may first appear later in childhood, or rarely, not until adulthood. Symptoms include poor weight gain and diarrhea along with abnormally shaped red blood cells (acanthocytosis). Affected children often have problems with balance, coordination, and walking due to problems with nerve function and muscle weakness. Anemia and a type of vision loss called Retinitis Pigmentosa may also occur.  Treatment to attempt to slow down the progression of symptoms includes supplementation with the fat-soluble vitamins and other supplements along with special low-fat medical diet. 

What causes Abetalipoproteinemia?

Abetalipoproteinemia is caused by a gene change, or mutation, in both copies of the MTTP gene pair. These mutations cause the genes to not work properly or not work at all.  The MTTP genes are important in helping the body absorb fats, cholesterol, and fat-soluble vitamins from the diet.  When both copies of the MTTP gene pair do not work correctly, it leads to the symptoms described above. 

Achondrogenesis, Type 1B

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What is Achondrogenesis, Type 1B?

Achondrogenesis, Type 1B is an autosomal recessive disorder that affects cartilage and bone. Signs and symptoms of this disorder include abnormal bone and joint development, a small rib cage that may cause breathing problems in the newborn period, short stature, short arms and legs, curvature of the spine (scoliosis), painful joints that restrict movement and early arthritis that worsens over time. Bone and cartilage abnormalities may also occur in the hands, feet, outer portions of the ears, head, and face. Intelligence is not affected. Currently there is no cure or specific treatment for Achondrogenesis, Type IB. 

Three other related but less common inherited disorders are sometimes caused by specific mutations in the same gene. Diastrophic Dysplasia includes short stature, joint restrictions (contractures), cleft palate and other minor features. Atelosteogenesis Type 2 has symptoms similar to Diastrophic Dysplasia but is fatal in the newborn period. Recessive Multiple Epiphyseal Dysplasia includes short stature, joint pain, curvature of the spine, abnormalities of the hands, feet, and knees, and sometimes other birth defects.  

What causes Achondrogenesis, Type 1B?

Achondrogenesis, Type 1B is caused by a gene change, or mutation, in both copies of the SCL26A2 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. 

Achromatopsia, CNGB3-Related

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What is Achromatopsia, CNGB3-Related?

Achromatopsia, CNGB3-Related is an autosomal recessive condition that causes partial or complete loss of color vision.  Most people with this condition have complete Achromatopsia, and can only see in shades of black, white, and gray.  Other vision problems seen with Achromatopsia, CNGB3-Related include light sensitivity, reduced sharpness of vision, involuntary shaking movements of the eye (nystagmus), farsightedness or, less commonly, nearsightedness. It is common for light sensitivity and nystagmus to appear within the first few weeks or months of life, although this may improve slightly over time.  Achromatopsia, CNGB3-Related is not the same as colorblindness, a condition where color can be seen but it is difficult to distinguish between certain colors. Currently there is no cure for this condition. Although rare, some individuals will have incomplete Achromatopsia with the ability to perceive some color. Also rare is another form of the disorder called Progressive Cone Dystrophy where loss of color doesn’t begin until childhood or teenage years.

What causes Achromatopsia, CNGB3-Related?

Achromatopsia, CNGB3-Related is caused by mutations in both copies of the CNGB3 gene pair. These mutations cause the CNGB3 genes to not work properly or not work at all.  When both copies of the CNGB3 gene pair do not work correctly, it causes the symptoms described above. 

Acrodermatitis Enteropathica

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What is Acrodermatitis Enteropathica?

Acrodermatitis Enteropathica is an autosomal recessive disorder that causes a deficiency of zinc in the body. People with this condition cannot absorb zinc from food.  If the condition is not treated, symptoms appear in infancy and include irritability, diarrhea, hair loss, poor growth, abnormal nails, recurrent infections, and irritation of the skin called dermatitis. The skin problems, which include dry scaly skin and pimple-like lesions that may blister, occur most often around the mouth and anus. Psychological and neurological problems may also occur. Treatment with zinc supplements can prevent or improve symptoms. People with this condition who are treated can often live healthy lives.  Without treatment this condition can be fatal.

What causes Acrodermatitis Enteropathica?

Acrodermatitis Enteropathica is caused by a gene change, or mutation, in both copies of the SLC39A4 gene pair.  These mutations cause the genes to not work properly or not work at all.  Normal function of the SLC39A4 genes is necessary for the body to absorb zinc. When both copies of the SLC39A4 gene do not work correctly, the body is unable to absorb zinc which leads to the symptoms described above. 

Acute Infantile Liver Failure, TRMU-Related

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What is Acute Infantile Liver Failure, TRMU-Related?

Acute Infantile Liver Failure, TRMU-Related is an autosomal recessive disorder that causes temporary life-threatening liver failure in infants. Signs and symptoms show up shortly after birth. Babies with this condition have problems with feeding, vomiting, irritability, jaundice, lethargy, a distended abdomen, and abnormal laboratory results showing acute liver failure. Although the condition can be fatal, with proper medical treatment most infants survive the acute episode of liver failure. Children who survive usually do not have any further episodes of liver failure and have normal growth and development.   

What causes Acute Infantile Liver Failure, TRMU-Related?

Acute Infantile Liver Failure, TRMU-Related is caused by a gene change, or mutation, in both copies of the TRMU gene pair. These mutations cause the genes to not work properly or not work at all. If both copies of the TRMU gene pair do not work correctly, it leads to the symptoms described above. 

Acyl-CoA Oxidase I Deficiency

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What is Acyl-CoA Oxidase I Deficiency?

Acyl-CoA Oxidase I Deficiency is an autosomal recessive disorder that causes the buildup of certain fatty substances in the body.  This causes damage to the brain that worsens with time.  Babies with this condition typically have problems feeding and gaining weight, poor muscle tone, seizures, and a distinctive facial appearance.  Some babies have extra fingers or toes, and some have an enlarged liver.  Over time, the coating around the nerves (myelin) in the brain and body break down.  This leads to loss of milestones and skills starting around the age of two years and intellectual and physical disabilities that worsen over time.  Hearing and vision loss may also occur. Lifespan is shortened and many children with Acyl-CoA Oxidase I Deficiency do not survive past childhood. Currently there is no cure for this condition.

What causes Acyl-CoA Oxidase I Deficiency?

Acyl-CoA Oxidase I Deficiency is caused by a gene change, or mutation, in both copies of the ACOX1 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.

Adrenoleukodystrophy, X-Linked

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What is Adrenoleukodystrophy, X-Linked?

Adrenoleukodystrophy (ALD), X-Linked is an X-linked inherited disorder found most often in boys that mainly affects the nervous system and the adrenal glands, the small organs located on top of each kidney. In this disorder, the fatty covering (called myelin) that protects the nerves in the brain and spinal cord starts to break down. This causes problems when the nerves send information to the brain. In addition, damage to the outer layer of the adrenal glands causes a lack of certain hormones. Lower amounts of these hormones may cause weakness, weight loss, skin changes, vomiting, and coma. It is more common for boys to be affected than girls.

There are three different types of ALD, X-Linked: a childhood cerebral form, an adrenomyeloneuropathy (AMN) type, and a form called Addison disease.

Childhood Cerebral Form: Children with this type of ALD have learning and behavior problems that usually begin between the age of 4 and 10 years. Other symptoms include vision problems, difficulty swallowing, and poor coordination, all of which worsen over time. In addition, the adrenal glands start working improperly, which can cause vomiting, weakness, or coma. This type of ALD can progress rapidly and lifespan is shortened.

AMN Type: People with this type of ALD develop progressive stiffness and weakness in their legs, urinary and reproductive tract problems, and problems with behavior and thinking starting in early adulthood or middle age. Most people with this type of ALD have adrenal glands that work improperly leading to vomiting, weakness, or coma. In some severely affected individuals, damage to the brain and nervous system leads to early death.

Addison disease: The first symptoms of Addison disease are vomiting and weakness or coma caused by improperly working adrenal glands. Symptoms can begin anytime between childhood and adulthood. By middle age, most people have additional symptoms of ALD.
 

What causes Adrenoleukodystrophy, X-Linked?

Adrenoleukodystrophy (ALD), X-Linked is caused by a change, or mutation, in the ABCD1 gene. This mutation causes the gene to not work properly or not work at all. People with ALD, X-Linked cannot break down certain fats called very long chain fatty acids (VLCFAs). These fats build up in the body and can damage the adrenal glands and fatty covering around the nerves and brain and leads to the signs and symptoms of ALD, X-Linked. 

Aicardi-Goutières Syndrome

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What is Aicardi-Goutières Syndrome?

Aicardi-Goutières Syndrome is an autosomal recessive disorder that affects the brain, immune system, and the skin. Symptoms often first appear in infancy and include severe irritability, poor feeding, vomiting, fever, and seizures.  Episodes of brain inflammation (encephalopathy) cause slowed brain growth and small head size (microcephaly), delayed development, loss of skills, and inability to walk.  Most children with Aicardi-Goutières Syndrome have severe intellectual disability, muscle stiffness (spasticity), involuntary muscle spasms called dystonia, and abnormal eye movements. They may also have painful or itchy skin patches called chilblains on their fingers, toes and ears. Lifespan is shortened. Children with this condition often do not survive past childhood, although people with milder symptoms may live into adulthood.  Currently there is no cure or specific treatment for this condition.

What causes Aicardi-Goutières Syndrome?

Aicardi-Goutières Syndrome is caused by a gene change, or mutation, in the SAMHD1 gene.  These mutations cause the gene to not work properly or not work at all.  When both copies of the SAMHD1 gene do not work correctly, an abnormal immune and inflammatory response in the brain and skin occurs and leads to the symptoms described above.  

Alpha-Mannosidosis

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What is Alpha-Mannosidosis?

Alpha-Mannosidosis is an autosomal recessive disorder that causes toxic buildup of certain types of sugars, called oligosaccharides, in the body.  There are mild and severe forms of Alpha-Mannosidosis with signs and symptoms typically beginning in infancy or later in childhood.  In rare cases, symptoms may not begin until adulthood.  Many parts of the body are affected leading to distinctive facial features, intellectual disability, developmental delays, bone abnormalities, movement problems, muscle weakness, joint problems, frequent infections, psychiatric problems, and hearing loss.  The condition worsens with time.  People with Alpha-Mannosidosis often require a wheelchair.  Death may occur in childhood; however life-span may be near normal in individuals with a milder form of the condition. 

What causes Alpha-Mannosidosis?

Alpha-Mannosidosis is caused by a change, or mutation, in both copies of the MAN2B1 gene pair.  These mutations cause the genes to not work properly or not work at all.  The function of the MAN2B1 genes is to create an enzyme that breaks down certain sugars and clears them from the body. When both copies of this gene pair do not work properly, it causes buildup of specific sugars in the body causing cell damage in many organs. This leads to the symptoms described above.

Alpha-Thalassemia

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What is Alpha-Thalassemia?

Alpha-Thalassemia refers to a group of autosomal recessive inherited blood disorders that result in a reduction in the amount of hemoglobin, the protein in red blood cells that carries oxygen to cells throughout the body. A person with one of the Alpha-Thalassemia diseases has lifelong anemia. Mild anemia can lead to tiredness, irritability, dizziness, lightheadedness and a rapid heartbeat. Severe anemia can be life threatening and may require routine blood transfusions.  The most severe form is lethal during pregnancy or shortly after birth.

What causes Alpha-Thalassemia?

Hemoglobin is made of both alpha globin and beta globin proteins. There are four HBA genes that are responsible for making alpha globin.  Alpha-Thalassemia occurs when three or more of these four HBA genes is missing or changed or when a person has changes, or mutations, called Constant Spring mutations, in two of the four genes. The exact type of Alpha-Thalassemia a person has depends on how many of the HBA (alpha globin) genes are not working. Some common types of Alpha-Thalassemia are:

Hemoglobin H Disease: caused by three missing or changed alpha globin genes. A person who has three missing or changed alpha globin genes has Hemoglobin H Disease. Hemoglobin H Disease can be mild or severe. People with severe disease may have chronic anemia, liver disease, and bone changes. Some people with Hemoglobin H Disease require frequent blood transfusions and other treatments.

Hemoglobin H-Constant Spring Disease: caused by two missing alpha globin genes and one Constant Spring mutation. A person with these gene findings has Hemoglobin H-Constant Spring Disease. This condition is usually more severe than Hemoglobin H Disease. A person with this condition typically has chronic anemia, is more likely to need blood transfusions, has more frequent viral infections, and may have an enlarged spleen.

Homozygous Constant Spring Disease: caused by two Constant Spring mutations. A person with Homozygous Constant Spring Disease has mild to severe anemia and symptoms similar to those seen in Hemoglobin H Disease described above.

Alpha-Thalassemia Major, also known as Hemoglobin Bart’s Disease: caused by four missing or changed alpha globin genes. This results in very severe anemia. Affected babies develop symptoms before birth and, in most cases, are either stillborn or do not survive the newborn period. Mothers pregnant with a fetus with Alpha-Thalassemia Major can develop health problems during pregnancy.

Alpha-Thalassemia Intellectual Disability Syndrome

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What is Alpha-Thalassemia Intellectual Disability Syndrome?

Alpha-Thalassemia Intellectual Disability (ATRX) Syndrome is a rare X-linked disorder that affects mainly boys. It causes significant intellectual disability and delays in all areas of development. Many boys with this condition speak few, if any, words and some are unable to walk on their own. Common features of this condition include a smaller than average head size, short stature, clubbed feet, abnormalities of the genitals, and muscle weakness (hypotonia). About 85% of boys with Alpha-Thalassemia Intellectual Disability Syndrome also have a blood disorder called Alpha-Thalassemia, a type of anemia. Although some children with this condition are less severely affected than others, most need lifelong medical treatment.

What causes Alpha-Thalassemia Intellectual Disability Syndrome?

Alpha-Thalassemia Intellectual Disability Syndrome is caused by a change, or mutation, in the ATRX gene. This mutation causes the gene to not work properly or not work at all, which results in the symptoms described above. 

Alport Syndrome, COL4A3-Related

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What is Alport Syndrome, COL4A3-Related?

Autosomal recessive Alport Syndrome, COL4A3-Related is an inherited disorder that affects the kidneys, eyes, and ears. This condition causes progressive loss of kidney function which leads to blood and protein in the urine. Over time, the kidneys no longer work properly and dialysis or kidney transplant is often needed, typically in early to late adulthood. Sensorineural hearing loss usually occurs by late childhood or early teens, but hearing aids are helpful.  Eye problems include increased risk for cataracts, abnormally shaped lenses, and wearing away of the cornea.  People with Alport syndrome often need glasses, but it is rare for them to have vision loss. 

Autosomal dominant Alport Syndrome, COL4A3-Related is a less common form of this disorder caused by a mutation in the same gene.  People with the autosomal dominant form have less severe symptoms that progress more slowly.  Kidney disease and hearing loss may not occur until late adulthood and eye problems are rare. 

What causes Alport Syndrome, COL4A3-Related?

Autosomal recessive Alport Syndrome, COL4A3-Related is caused by a gene change, or mutation, in both copies of the COL4A3 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 of autosomal recessive Alport Syndrome, COL4A3-Related described above. 

Some cases of Alport Syndrome, COL4A3-Related are inherited in an autosomal dominant manner.  This means that a person who has a mutation in just one copy of the COL4A3 gene is affected with Alport Syndrome and has symptoms of Alport Syndrome. 

Alport Syndrome, COL4A4-Related

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What is Alport Syndrome, COL4A4-Related?

Autosomal recessive Alport Syndrome, COL4A4-Related is an inherited disorder that affects the kidneys, eyes, and ears. This condition causes progressive loss of kidney function which leads to blood and protein in the urine. Over time, the kidneys can no longer work properly and dialysis or kidney transplant is often needed, typically in early to late adulthood. Sensorineural hearing loss usually occurs by late childhood or early teens, but hearing aids are helpful.  Eye problems include increased risk for cataracts, abnormally shaped lenses, and wearing away of the cornea.  People with Alport Syndrome often need glasses, but it is rare for them to have vision loss. 

Autosomal dominant Alport Syndrome, COL4A4-Related is a less common form of this disorder caused by a mutation in the same gene.  People with the autosomal dominant form have less severe symptoms that progress more slowly.  Kidney disease and hearing loss may not occur until late adulthood and eye problems are rare. 

What causes Alport Syndrome, COL4A4-Related?

Autosomal recessive Alport Syndrome, COL4A4-Related is caused by a gene change, or mutation, in both copies of the COL4A4 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 of autosomal recessive Alport Syndrome, COL4A4-Related described above. 

Some cases of Alport Syndrome, COL4A4-Related are inherited in an autosomal dominant manner.  This means that a person who has a mutation in just one copy of the COL4A4 gene is affected with Alport Syndrome and has symptoms of autosomal dominant Alport Syndrome. 

Alport Syndrome, X-Linked

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What is Alport Syndrome, X-Linked?

Alport Syndrome, X-Linked is an X-linked inherited condition that affects the kidneys, ears, and eyes. Alport Syndrome, X-Linked causes progressive loss of kidney function which leads to blood and protein in the urine. Over time, the kidneys can no longer work properly and dialysis or kidney transplant is often needed, typically in early to late adulthood. Sensorineural hearing loss usually occurs by late childhood or early teens, but hearing aids are typically effective. Eye problems include increased risk for cataracts, abnormally shaped lenses, and wearing away of the cornea. People with Alport Syndrome, X-Linked often need glasses, but it is rare for them to have vision loss.  Alport Syndrome, X-Linked is more common in boys than girls. 

What causes Alport Syndrome, X-Linked?

Alport Syndrome, X-Linked is caused by a change, or mutation, in the COL4A5 gene. This mutation causes the gene to not work properly or not work at all.  The normal function of the COL4A5 gene is to help make Type IV collagen. Type IV collagen is needed in the kidney, inner ear, and eye in order for these organs to work properly.   When the COL4A5 gene is not working correctly in a male, it leads to the symptoms described above. 

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