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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

Limb-Girdle Muscular Dystrophy, Type 2I

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What is Limb-Girdle Muscular Dystrophy, Type 2I?

Limb-Girdle Muscular Dystrophy, Type 2I is autosomal recessive.  It is one of a group of autosomal recessive disorders that affect the muscles of the hips and shoulders.  Over time, Limb-Girdle Muscular Dystrophy Type 2I leads to weakness and breakdown (atrophy) of the pelvic, hip, thigh, shoulder, and upper arm muscles. Symptoms vary from person to person but usually begin in childhood or early adulthood and worsen slowly over many years. Muscle weakness and atrophy lead to difficulty in walking, running, and getting up from the floor.  Over time, some people with this condition need the use of a wheelchair.  As the disease progresses, kidney, heart, and joint problems, as well as breathing difficulties may occur. 

Less often, mutations in the same pair of genes cause a related but more severe disorder called Walker-Warburg Syndrome.  Walker-Warburg Syndrome causes abnormalities of the brain and eyes along with severe muscle weakness that begins in infancy.  Babies with this condition who have brain abnormalities usually do not live past early childhood.  Some children do not have the brain and eye abnormalities and may live longer, although life span is still shortened.  Currently there is no cure for these conditions and treatment is based on symptoms.

What causes Limb-Girdle Muscular Dystrophy, Type 2I?

Limb-Girdle Muscular Dystrophy, Type 2I is caused by a gene change, or mutation, in both copies of the FKRP gene pair.  These mutations cause the genes to not work properly or not work at all.  Normal function of the FKRP gene is important for healthy muscle development.  When both copies of the FKRP gene pair do not work correctly, it leads to the symptoms described above.  It is sometimes, but not always, possible to determine whether a specific mutation in the FKRP gene will cause Limb-Girdle Muscular Dystrophy, Type 2I or Walker-Warburg Syndrome. 

Lipoamide Dehydrogenase Deficiency (Dihydrolipoamide Dehydrogenase Deficiency)

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What is Lipoamide Dehydrogenase Deficiency (Dihydrolipoamide Dehydrogenase Deficiency)?

Lipoamide Dehydrogenase Deficiency (also known as Dihydrolipoamide Dehydrogenase Deficiency or Maple Syrup Urine Disease Type 3) is an autosomal recessive disorder that causes the buildup of a toxic substance called lactic acid in the body. Symptoms often begin between one and six months of age and include rapid breathing and heartbeat, nausea and vomiting, low muscle tone (hypotonia), abnormal movements, lack of energy, and poor growth that sometimes leads to early death. Infants and children with Lipoamide Dehydrogenase Deficiency who survive often have developmental delay, intellectual disability, stiff muscles (spasticity), abnormal movements, and seizures. A special medical diet, supplements, and other medical treatments are used to try to slow down the progression of the symptoms but there is no cure. A less common form of this condition causes only liver disease which can progress over time to liver failure; symptoms can start as early as birth but often start later in adulthood.

What causes Lipoamide Dehydrogenase Deficiency (Dihydrolipoamide Dehydrogenase Deficiency)?

Lipoamide Dehydrogenase Deficiency is caused by a gene change, or mutation, in both copies of the DLD gene pair. These mutations cause the genes to not work properly or not work at all. When both copies of this gene are not working correctly, it leads to the symptoms described above.

Lipoid Adrenal Hyperplasia

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What is Lipoid Adrenal Hyperplasia?

Lipoid Adrenal Hyperplasia is a rare autosomal recessive disorder in which the adrenal glands cannot make certain steroid hormones. There are two forms of Lipoid Adrenal Hyperplasia; a classic form and a non-classic form. In the classic form, life-threatening symptoms begin within the first few months of life if not treated.  The lack of adrenal hormones causes severe salt loss in the urine, leading to dehydration and death unless hormone replacement is started.  Males with the classic form are born with external genitals that look female. This is caused by problems with sex hormone production. In the non-classic form, symptoms are less severe and start later in infancy or childhood and do not show the genital changes seen in the classic form.  Medical treatment with hormone replacement may help prevent or reduce symptoms of this condition.

What causes Lipoid Adrenal Hyperplasia?

Lipoid Adrenal Hyperplasia is caused by a gene change, or mutation, in both copies of the STAR gene pair.  These mutations cause the genes to not work properly or not work at all.  When both copies of the STAR gene do not work correctly, the body cannot make specific steroid hormones, leading to the symptoms described above.

Lipoprotein Lipase Deficiency

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What is Lipoprotein Lipase Deficiency?

Lipoprotein Lipase Deficiency is an autosomal recessive disorder in which the body either cannot make, or makes less of, an enzyme called lipoprotein lipase. Without normal amounts of this enzyme, the body cannot break down fat from food, which causes fat to build up in the blood. Symptoms of Lipoprotein Lipase Deficiency usually begin in childhood with episodes of abdominal pain, abnormally high levels of triglycerides (a form of fat) in the blood, enlarged spleen and liver, inflammation of the pancreas, and raised areas of fat under the of skin (xanthomas).  Treatment with a very low fat diet can prevent or lessen the symptoms. 

What causes Lipoprotein Lipase Deficiency?

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

Carriers for Lipoprotein Lipase Deficiency may have a moderate increase in triglyceride levels which may give them a slightly increased risk for early atherosclerosis. 

Long Chain 3-Hydroxyacyl-CoA Dehydrogenase Deficiency

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What is Long Chain 3-Hydroxyacyl-CoA Dehydrogenase Deficiency?

Long Chain 3-Hydroxyacyl-CoA Dehydrogenase (LCHAD) Deficiency is an autosomal recessive disorder in which the body cannot break down and use certain fats for energy.  Signs and symptoms of LCHAD Deficiency typically appear during infancy or early childhood and can include vomiting, lack of energy, weak muscle tone, and low blood sugar (hypoglycemia). The symptoms of LCHAD Deficiency are often triggered by going a long time without eating (fasting) or during illness. If the condition is not treated, children with LCHAD Deficiency are at risk for breathing problems, intellectual disability, enlarged heart and liver, vision loss, seizures, coma, and sudden death. Treatment includes a medical low-fat diet, avoidance of fasting, and other supplements that help prevent or lessen the symptoms. Even with careful treatment, some children still have repeated episodes of low blood sugar and other long-term health problems.

Rarely, mutations in the same gene pair cause a related disorder called Mitochondrial Trifunctional Protein Deficiency.  This disorder has similar symptoms to LCHAD Deficiency with similar treatment. There is an early-onset severe form that sometimes results in death, even with treatment; a childhood-onset form that needs lifelong treatment; and a rare milder form that causes muscle breakdown leading to cramping, weakness, pain, and red-brown colored urine but does not affect intelligence.

What causes Long Chain 3-Hydroxyacyl-CoA Dehydrogenase Deficiency?

Long Chain 3-Hydroxyacyl-CoA Dehydrogenase (LCHAD) Deficiency is caused by a gene change, or mutation, in both copies of the HADHA 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.

Women who are carriers for LCHAD Deficiency or Mitochondrial Trifunctional Protein Deficiency and are pregnant with an affected fetus are at risk to develop serious liver disorders called AFLP (acute fatty liver of pregnancy) and HELLP Syndrome (hemolysis, elevated liver enzymes, low platelets).  Signs and symptoms include pain in the abdomen, low blood sugar, ammonia in the blood, breakdown of red blood cells, and abnormal liver enzymes. 

Lysinuric Protein Intolerance

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What is Lysinuric Protein Intolerance?

Lysinuric Protein Intolerance is an autosomal recessive disorder in which certain building blocks of protein (amino acids) cannot be broken down correctly by the body. This leads to a toxic buildup of ammonia in the blood. Symptoms of Lysinuric Protein Intolerance usually first begin in infancy after the baby is weaned off breast milk or formula and starts eating solid food. Symptoms include nausea, vomiting, poor feeding and poor growth, aversion to protein-rich foods, poor muscle tone, brittle bones, enlarged liver and spleen, and lung and kidney problems. Treatment with a medical low-protein diet along with specific supplements and medications can lessen the severity of symptoms but cannot prevent them.

What causes Lysinuric Protein Intolerance?

Lysinuric Protein Intolerance is caused by a gene change, or mutation, in both copies of the SLC7A7 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.

Maple Syrup Urine Disease, Type 1A

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What is Maple Syrup Urine Disease, Type 1A?

Maple Syrup Urine Disease, Type 1A is an autosomal recessive disorder in which the body is unable to break down certain building blocks of protein from food.  Signs and symptoms usually begin in infancy and include poor feeding, vomiting, lack of energy, failure to grow at the normal rate, and developmental delay. Maple Syrup Urine Disease gets its name from the maple syrup odor of the urine in babies with the disease.   Symptoms may worsen after going a long time without food or with illness and can be life-threatening.  Lifelong dietary treatment is needed.  If untreated, Maple Syrup Urine Disease, Type 1A can lead to intellectual disability, seizures, coma, and sometimes death.  Even with treatment affected children continue to have symptoms of the disorder.  Some children have a milder form of Maple Syrup Urine Disease, Type 1A with fewer symptoms. 

What causes MSUD, Type 1A?

Maple Syrup Urine Disease, Type 1A is caused by a change, or mutation, in both copies of the BCKDHA gene pair.  These mutations cause the genes to not work properly or not work at all.  The function of the BCKDHA genes is to help breakdown certain building blocks of protein in food called amino acids.  When both copies of this gene pair do not work correctly, toxic buildup of certain amino acids occurs and causes damage to the brain and other organs. 

Maple Syrup Urine Disease, Type 1B

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What is Maple Syrup Urine Disease, Type 1B?

Maple Syrup Urine Disease, Type 1B is an autosomal recessive disorder in which the body is not able to break down certain building blocks of protein (amino acids) from food.  Signs and symptoms usually begin in infancy and include poor feeding, vomiting, lack of energy, failure to grow at the normal rate, and developmental delay.  Maple Syrup Urine Disease gets its name from the maple syrup odor of the urine in babies with the disease.  Symptoms may worsen after going a long time without food or with illness and can be life-threatening.  Lifelong dietary and medical treatment is needed.  If untreated, Maple Syrup Urine Disease, Type 1B can lead to intellectual disability, seizures, coma, and sometimes death.  Even with treatment some children continue to have symptoms of the disorder.  Some children have a milder form of Maple Syrup Urine Disease, Type 1B with fewer symptoms. 

What causes Maple Syrup Urine Disease, Type 1B?

Maple Syrup Urine Disease, Type 1B is caused by a gene change, or mutation, in both copies of the BCKDHB gene pair. These mutations cause the genes to not work properly or not work at all.  The function of the BCKDHB genes is to help breakdown certain building blocks of protein in food called amino acids.  When both copies of this gene pair do not work correctly, toxic buildup of certain amino acids occurs and causes damage to the brain and other organs. 

Meckel-Gruber Syndrome, Type 1

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What is Meckel-Gruber Syndrome, Type 1?

Meckel-Gruber Syndrome, Type 1 (also called Meckel Syndrome, Type 1) is an autosomal recessive disorder that causes birth defects in many parts of the body.  Affected infants have an encephalocele (bulging of part of the brain through an opening in the back of the skull), small head with sloping forehead, abnormal kidneys with many cysts (fluid-filled sacs), and extra fingers and toes.  Affected babies may also have other birth defects including cleft lip and/or cleft palate, underdeveloped eyes, liver abnormalities, and underdeveloped or abnormal genitals.  There is no cure for Meckel-Gruber Syndrome, Type 1 and most babies die shortly after birth due to the severity of the health problems associated with this disorder.

Rarely, mutations in the same gene pair cause a related disorder called Bardet-Biedl Syndrome 13.  This disorder causes loss of vision, obesity, diabetes, high blood pressure, high cholesterol, developmental delay, intellectual disability, extra fingers and toes, kidney problems, genital abnormalities and reduced amounts of sex hormones.  

What causes Meckel-Gruber Syndrome, Type 1?

Meckel-Gruber Syndrome, Type 1 is caused by a gene change, or mutation, in both copies of the MKS1 gene pair. These mutations cause the genes to not work properly or not work at all. When both copies of the MKS1 gene pair do not work correctly, it leads to the symptoms described above. 

It is sometimes, but not always, possible to tell whether a specific gene mutation will cause Meckel-Gruber Syndrome, Type 1 or Bardet-Biedl Syndrome 13. 

Medium Chain Acyl-CoA Dehydrogenase Deficiency

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What is Medium Chain Acyl-CoA Dehydrogenase Deficiency?

Medium Chain Acyl-CoA Dehydrogenase Deficiency is an autosomal recessive disorder that causes the body to be unable to break down certain types of fat. It is one of a group of inherited conditions called fatty acid oxidation disorders.  Children born with Medium Chain Acyl-CoA Dehydrogenase Deficiency are unable to change some of the fats from food that they eat into energy that the body needs to function properly. As a result, fatty acids build up in the body.  If left untreated, this disorder can lead to health problems such as seizures, breathing problems, liver problems, brain damage, coma, and even death.  With diagnosis and treatment early in life, people with Medium Chain Acyl-CoA Dehydrogenase Deficiency can often lead healthy lives.  Some people with Medium Chain Acyl-CoA Dehydrogenase Deficiency have milder symptoms or no symptoms at all.

What causes Medium Chain Acyl-CoA Dehydrogenase Deficiency?

Medium Chain Acyl-CoA Dehydrogenase Deficiency is caused by a gene change, or mutation in both copies of the ACADM gene pair.  These mutations cause the genes to not work properly or not work at all.  The function of the ACADM genes is to make an enzyme called medium-chain acyl-CoA dehydrogenase, which is needed to break down a type of fat, called medium-chain fatty acids, found in food and the body’s fat stores.  When both copies of this gene do not work correctly, it can lead to the symptoms described above.

Megalencephalic Leukoencephalopathy with Subcortical Cysts

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What is Megalencephalic Leukoencephalopathy with Subcortical Cysts?

Megalencephalic Leukoencephalopathy with Subcortical Cysts is an autosomal recessive disorder that affects the brain and nervous system. Signs and symptoms begin in infancy or childhood and include large head and brain size, developmental delays, loss of developmental skills, problems with coordination and movement, muscle stiffness, seizures, speech problems, and mild to moderate intellectual disability. Some people with this condition can walk without assistance and others eventually need a wheelchair.   Currently there is no cure for this disorder and treatment is based on symptoms.

What causes Megalencephalic Leukoencephalopathy with Subcortical Cysts?

Megalencephalic Leukoencephalopathy with Subcortical Cysts is caused by a gene change, or mutation, in both copies of the MLC1 gene pair. These mutations cause the genes to not work properly or not work at all. Normal function of the MLC1 genes is important for development of the brain and nerves. When both copies of the MLC1 gene do not work correctly, it leads to the symptoms described above. 

Menkes Syndrome

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What is Menkes Syndrome?

Menkes Syndrome is a severe X-linked inherited disorder that affects mainly boys. Signs and symptoms often start in infancy and include sparse light-colored and kinky hair, lax skin, growth delays, poor muscle tone (hypotonia), bladder infections, seizures, developmental delay, intellectual disability, breathing problems, and strokes. Currently there is no cure for Menkes Syndrome. Treatment with copper supplements can help lessen the symptoms in some children with Menkes; however, even with careful treatment, many children do not live beyond 3 years of age.

Rare individuals have a milder form of Menkes Syndrome sometimes called Occipital Horn Syndrome or X-Linked Cutis Laxa. Signs and symptoms of Occipital Horn Syndrome usually begin in childhood and include calcified wedges near the back of the head (occipital horns), lax skin, flexible joints, hernias, twisted blood vessels, and chronic diarrhea. Some people with Occipital Horn Syndrome have mild intellectual disability. Lifespan may be shortened but most people live until adulthood. Even more rarely, a different form of the disorder, called ATP7A-Related Distal Motor Neuropathy (or Spinal Muscular Atrophy, Distal, X-Linked 3), may occur. Symptoms of Distal Motor Neuropathy usually begin in adulthood but may appear earlier in childhood and include worsening muscle weakness and wasting (atrophy) of the hands and feet, difficulty walking, lack of reflexes in the ankles, and lack of sensation in the fingers and toes. Other symptoms may include hammer toes, curled fingers, and an abnormally high arch of the foot (pes cavus).

What causes Menkes Syndrome?

Menkes Syndrome is caused by a change, or mutation, in the ATP7A gene, which causes the gene to not work properly or not work at all. When this gene does not work correctly in a male, it leads to Menkes Syndrome or one of the rare related disorders described above. 

Metachromatic Leukodystrophy, ARSA-Related

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What is Metachromatic Leukodystrophy, ARSA-Related?

Metachromatic Leukodystrophy (MLD), ARSA-Related is an autosomal recessive disorder that affects the brain and nervous system.  MLD, ARSA-Related causes a buildup of a specific type of fat in the cells of the body.  This causes myelin, the substance that covers and protects nerves, to break down over time.  Without myelin, brain and nerve cells no longer work properly. There are 3 forms of MLD, ARSA-Related: the late infantile form usually shows symptoms by age 2; the juvenile form starts in childhood or early adolescence; and the adult form starts in young adulthood.  Symptoms of MLD, ARSA-Related include loss of cognitive and motor skills, behavior and personality changes, seizures, dementia, and loss of hearing, vision, and speech, all of which worsen over time. The condition eventually leads to paralysis and loss of responsiveness. Lifespan is shortened, especially with the early-onset forms.  Currently there is no cure for MLD, ARSA-Related and treatment is based on symptoms.

What causes Metachromatic Leukodystrophy, ARSA-Related?

MLD, ARSA-Related is caused by a gene change, or mutation, in both copies of the ARSA 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.

Metachromatic Leukodystrophy, PSAP-Related

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What is Metachromatic Leukodystrophy, PSAP-Related?

Metachromatic Leukodystrophy, PSAP-Related is an autosomal recessive disorder that affects many parts of the body. Signs and symptoms usually begin in childhood. Symptoms include anemia, easy bruising, fatigue, bone problems including bone pain and breaks, enlarged liver and spleen, and lung disease. Some children will also have symptoms involving the brain and nervous system including seizures, developmental delays, intellectual disability, abnormal eye movements, and problems with coordination and movement. The symptoms may worsen over time.

Very rarely, mutations in the same gene cause a related disorder, either Gaucher Disease, atypical, Krabbe Disease, atypical, or Combined SAP Deficiency. Symptoms of these disorders include a severely enlarged liver and spleen along with brain and nervous system problems that are similar to or more severe than those described above. Babies with either Krabbe Disease, atypical or Combined SAP Deficiency have very severe symptoms starting from birth and usually die in infancy or early childhood. People with Gaucher Disease, atypical may start having symptoms in childhood or not until early adulthood. Currently there is no cure for any of these disorders and treatment is based on symptoms.

What causes Metachromatic Leukodystrophy, PSAP-Related?

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

Methylmalonic Aciduria and Homocystinuria, Type cblC

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What is Methylmalonic Aciduria and Homocystinuria, Type cblC?

Methylmalonic Aciduria refers to a group of autosomal recessive conditions with many different forms, each of which has different causes and treatments. The type described here is Methylmalonic Aciduria and Homocystinuria, Type cblC. In this disorder the body is not able to use vitamin B12 (cobalamin) correctly to break down certain types of fat and protein from food.  Symptoms of Methylmalonic Aciduria and Homocystinuria, Type cblC usually begin in the first month of life and can include growth delay, small head size, skin rash, vomiting, feeding problems, fever, lethargy (extreme tiredness), weak muscle tone (hypotonia), and vision loss due to damage to the retina.  Lifelong dietary and medical treatments are needed for this disorder.  If left untreated, death in infancy or childhood may occur.  Some people with this disorder have a milder form with onset in adulthood. 

What causes Methylmalonic Aciduria and Homocystinuria, Type cblC?

Methylmalonic Aciduria and Homocystinuria, Type cblC is caused by a gene change, or mutation in both copies of the MMACHC 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, the body cannot use Vitamin B12 properly to break down certain fats and proteins in the diet.  This causes a toxic buildup of the amino acids methylmalonic acid and homocysteine the body, which causes the symptoms described above.

Methylmalonic Aciduria and Homocystinuria, Type cblD

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What is Methylmalonic Aciduria and Homocystinuria, Type cblD?

Methylmalonic Aciduria refers to a group of autosomal recessive conditions with many different forms, each of which has different causes and treatments. The type described here is Methylmalonic Aciduria and Homocystinuria, Type cblD.  In this disorder, the body cannot use vitamin B12 (cobalamin) correctly to break down certain types of fat and protein from food.  This causes the buildup of toxic substances in the blood and can lead to serious health problems. Symptoms include small head size, poor appetite and growth, lack of energy, low muscle tone (hypotonia), eye abnormalities, developmental delay, anemia, neurological problems, seizures, and intellectual deficit. Symptoms vary and can begin before birth or not until adulthood. In most cases, symptoms start in infancy and often become worse after going a long time without food or during illness.  Some children have symptoms of either Homocystinuria or Methylmalonic Acidemia but not both. For some children, medical treatment including vitamin B12 injections, other supplements, and a special diet may help reduce the severity of this disorder.

What causes Methylmalonic Aciduria and Homocystinuria, Type cblD?

Methylmalonic Aciduria and Homocystinuria, Type cblD is caused by a change, or mutation, in both copies of the MMADHC 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, the body cannot use Vitamin B12 properly to break down certain fats and proteins in the diet.  This causes a toxic buildup of the amino acids methylmalonic acid and/or homocysteine the body, which causes the symptoms described above.

Methylmalonic Aciduria, MMAA-Related

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What is Methylmalonic Aciduria, MMAA-Related?

Methylmalonic Aciduria refers to a group of autosomal recessive disorders in which the body cannot break down certain proteins and fats from food.  This leads to the lack of energy for the body and a buildup of toxic substances in the blood. There are many forms of this Methylmalonic Aciduria, each caused by mutations in a different gene, one of which is MMAA. Symptoms of Methylmalonic Aciduria, MMAA-Related usually start in infancy or childhood and often include episodes of feeding and breathing problems, vomiting, weak muscle tone, and lack of energy. Episodes often start during illness or stress, going a long time without food, or eating too much protein.  If these episodes are not treated, they can lead to seizures, stroke, or coma and can sometimes be life-threatening. Children with this condition may also have slow weight gain and growth, and developmental delay. Methylmalonic Aciduria, MMAA-Related is sometimes referred to as ‘vitamin B12 responsive’, meaning that it can often be treated with vitamin B12 injections. Vitamin B12, along with a special diet and other medical treatments, can help prevent further symptoms but cannot correct any problems that have already occurred.

What causes Methylmalonic Aciduria, MMAA-Related?

Methylmalonic Aciduria, MMAA-Related is caused by a change, or mutation, in both copies of the MMAA 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.

Methylmalonic Aciduria, MMAB-Related

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What is Methylmalonic Aciduria, MMAB-Related?

Methylmalonic Aciduria refers to a group of autosomal recessive disorders in which the body cannot break down certain proteins and fats from food.  This leads to the lack of energy for the body and a buildup of toxic substances in the blood. There are many forms of this disorder, each caused by mutations in a different gene, one of which is MMAB. Symptoms of Methylmalonic Aciduria, MMAB-Related usually start in infancy or childhood and may include episodes of breathing problems, feeding problems and vomiting, weak muscle tone, and lack of energy.  Episodes often start during illness or stress, going a long time without food, or eating too much protein.  If these episodes are not treated, they can lead to seizures, stroke, or coma and can sometimes be life-threatening. Children with this condition may also have slow weight gain and growth, and developmental delay. Methylmalonic Aciduria, MMAB-Related is sometimes referred to as ‘vitamin B12 responsive’, meaning that it can sometimes be treated with vitamin B12 injections. Vitamin B12, along with a special diet and other medical treatments, may help prevent further symptoms in some children but cannot correct any problems that have already occurred.

What causes Methylmalonic Aciduria, MMAB-Related?

Methylmalonic Aciduria, MMAB-Related is caused by a change, or mutation, in both copies of the MMAB 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.

Methylmalonic Aciduria, Type mut(0)

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What is Methylmalonic Aciduria, Type mut(0)?

Methylmalonic Aciduria refers to a group of autosomal recessive disorders in which the body cannot break down certain proteins and fats from food.  This leads to the lack of energy for the body and a buildup of toxic substances in the blood. There are many forms of this disorder, each caused by mutations in a different gene, one of which is MUT.  Methylmalonic Aciduria, Type mut(0), is the most common and severe form with symptoms usually first starting in infancy.  Infants quickly start to show symptoms of vomiting, dehydration, breathing problems, and lack of energy.  Other symptoms that develop over time include enlarged liver, weak muscle tone, feeding problems, intellectual disability, kidney disease, and inflammation of the pancreas (pancreatitis). Without treatment, Methylmalonic Aciduria, Type mut(0) can be life-threatening. Treatment can sometimes reduce the severity of symptoms, but there is no cure for this disorder.

What causes Methylmalonic Aciduria, Type mut(0)?

Methylmalonic Aciduria, Type mut(0)  is caused by a change, or mutation, in both copies of the MUT gene pair.  These mutations cause the genes to not work properly or not work at all.  When both copies of the MUT gene do not work correctly, it leads to the symptoms described above.

Microphthalmia/Anophthalmia, VSX2-Related

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What is Microphthalmia/Anophthalmia, VSX2-Related?

Microphthalmia/Anophthalmia, VSX2-Related is an autosomal recessive disorder that causes specific birth defects of the eyes. Microphthalmia is when one or both eyes are smaller than average at birth and vision is impaired. Anophthalmia is when one or both eyes are absent at birth and there is no vision. An infant can be born with microphthalmia in one eye and anophthalmia in the other eye, the same type of birth defect in both eyes, or have just one affected eye. Children with this disorder may also have other abnormalities of the eye including cataracts, cysts, abnormalities of the cornea, and colobomas (a birth defect in the lens, iris, or retina).

What causes Microphthalmia/Anophthalmia, VSX2-Related?

Microphthalmia/Anophthalmia, VSX2-Related is caused by a change, or mutation, in both copies of the VSX2 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.

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