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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

Retinitis Pigmentosa 28

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What is Retinitis Pigmentosa 28?

Retinitis Pigmentosa 28 is autosomal recessive.  It is one of a group of inherited eye disorders in which the retina, the area at the back of the eye that allows you to see, gradually stops working.  Retinitis Pigmentosa 28 causes progressive vision loss.  The age at which symptoms begin and the severity of the condition varies from person to person. The first symptom is usually loss of night vision.  Over time, loss of peripheral vision (tunnel vision) develops. Then, loss of central vision occurs.  Retinitis Pigmentosa 28 affects only the vision.  Currently there is no cure or specific treatment to prevent the vision loss. 

What causes Retinitis Pigmentosa 28?

Retinitis Pigmentosa can be caused by mutations in one of a number of different genes with different inheritance patterns.  Retinitis Pigmentosa 28 is caused by a gene change, or mutation, in both copies of the FAM161A 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 results in the progressive vision loss described above.

Retinitis Pigmentosa 59

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What is Retinitis Pigmentosa 59?

Retinitis Pigmentosa 59 is autosomal recessive.  It is one of a group of inherited eye disorders in which the retina, the area at the back of the eye that allows you to see, gradually stops working.  Retinitis Pigmentosa 59 causes progressive vision loss.  The age at which symptoms begin and the severity of the condition varies from person to person. The first symptom is usually loss of night vision.  Over time, loss of peripheral vision (tunnel vision) develops. Then, loss of central vision occurs.  Retinitis Pigmentosa 59 affects only the vision.  Currently there is no cure or specific treatment to prevent the vision loss. 

What causes Retinitis Pigmentosa 59?

Retinitis Pigmentosa can be caused by mutations in one of a number of different genes with different inheritance patterns. Retinitis Pigmentosa 59 is caused by a gene change, or mutation, in both copies of the DHDDS 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 results in the progressive vision loss described above.

Rhizomelic Chondrodysplasia Punctata, Type 1

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What is Rhizomelic Chondrodysplasia Punctata, Type 1?

Rhizomelic Chondrodysplasia Punctata, Type 1 is an autosomal recessive disorder that causes severe problems with bone growth (dwarfism) which are present at birth. Other symptoms include distinct facial features, severe intellectual disability, developmental delay, and breathing problems. Many children born with this disorder die before age two.

Rarely, specific mutations in the same gene cause a different inherited condition called Refsum Disease 2. Signs and symptoms of Refsum Disease 2 include absence of smell and retinitis pigmentosa (gradual vision loss due to buildup of pigment in the retina). Some people with Refsum Disease 2 also have abnormalities of the bones in the hands and feet, muscle weakness, coordination and balance problems, hearing loss, ichthyosis (scaly dry skin), and heart problems. Intelligence is not affected.

What causes Rhizomelic Chondrodysplasia Punctata, Type 1?

Rhizomelic Chondrodysplasia Punctata, Type 1 is caused by a gene change, or mutation, in both copies of the PEX7 gene pair. These mutations cause the genes to not work properly or not work at all. The PEX7 genes help break down different substances stored in the parts of our cells called peroxisomes. When both copies of this gene pair do not work correctly, it causes the buildup of harmful substances in the cells of the body, which leads to the symptoms described above.

Rhizomelic Chondrodysplasia Punctata, Type 3

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What is Rhizomelic Chondrodysplasia Punctata, Type 3?

Rhizomelic Chondrodysplasia Punctata, Type 3 (also called Akyl-DHAP Synthase Deficiency) is an autosomal recessive disorder that causes abnormal bone growth which is present at birth. Children with this condition have a type of short stature called dwarfism where the upper arms and legs are short but the trunk is not. Other signs and symptoms of this condition include distinct facial features, joint pain and stiffness, developmental delays, severe intellectual disability, cataracts, and life-threatening breathing problems. There is no cure for this condition and death often occurs before the age of 10.

What causes Rhizomelic Dysplasia Punctata, Type 3?

Rhizomelic Chondrodysplasia Punctata, Type 3 is caused by a gene change, or mutation, in both copies of the AGPS 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. 

Roberts Syndrome

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What is Roberts Syndrome?

Roberts Syndrome is an autosomal recessive disorder that affects many parts of the body.  Signs and symptoms include poor growth (both before and after birth), mild to severe intellectual disability, abnormal knee and elbow joints, and severe birth defects of the bones of the arms, legs, fingers, and toes where the bones and digits may be either shortened or missing.  Birth defects of the face can include a cleft lip, cleft palate, small chin, and small head (microcephaly).  People with Roberts Syndrome may also have heart, kidney and genital problems. Symptoms vary from person to person and may be mild or severe. Infants with severe symptoms are often either stillborn or die in the newborn period.  People with milder symptoms often live into adulthood. There is no cure or specific treatment for this condition.

What causes Roberts Syndrome?

Roberts Syndrome is caused by a change, or mutation, in both copies of the ESCO2 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.

Salla Disease

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What is Salla Disease?

Salla Disease, one form of Sialic Acid Storage Disease, is an autosomal recessive disorder that mainly affects the nervous system. Most infants with Salla Disease appear normal at birth. Then during infancy signs and symptoms begin to appear including slowly progressing loss of skills, poor muscle tone (hypotonia) that changes with time to tight and stiff muscles (spasticity), seizures, developmental delay,  intellectual disability, speech problems, coordination problems (ataxia), and slow involuntary movements (athetosis) of the arms and legs.  Although symptoms vary from person to person, about two-thirds of people with Salla Disease are not able to walk. Most people with Salla Disease live into adulthood. Currently there is no cure for this condition and treatment is based on the symptoms.

What causes Salla Disease?

Salla Disease is caused by a gene change, or mutation, in both copies of the SLC17A5 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. 

Sandhoff Disease

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What is Sandhoff Disease?

Sandhoff Disease is an autosomal recessive disorder that affects the brain and nervous system.  Signs and symptoms usually start in the first year of life and include muscle weakness and loss of motor skills (sitting, crawling, and walking).  Over time, progressive brain damage, seizures, vision and hearing loss, intellectual disability, and paralysis occur.  Death usually occurs in early childhood. In rare cases, symptoms do not begin until the late teenage or adult years.  Symptoms of Late-Onset Sandhoff Disease include muscle weakness in the legs and coordination problems, psychiatric illness, and the gradual loss of motor skills that may lead to problems with speech, swallowing, and walking. In some cases, affected individuals have been treated with stem cell transplantation from cord blood or bone marrow. Couples at risk of having an affected child may consider cord blood banking, as siblings have a higher chance of being a match for stem cell transplantation than a non-related individual.

What causes Sandhoff Disease?

Sandhoff Disease is caused by a gene change, or mutation, in both copies of the HEXB 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.

Schimke Immunoosseous Dysplasia

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What is Schimke Immunoosseous Dysplasia?

Schimke Immunoosseous Dysplasia is an autosomal recessive disorder that causes abnormalities of the bones and a type of short stature called dwarfism.  Signs and symptoms vary from mild to severe and may be present at birth or not until later in childhood.  Typical symptoms include flat spine bones (vertebrae) that cause a short trunk and neck, growth delays, kidney disease that worsens to kidney failure, and a weakened immune system leading to repeated infections that can be life-threatening.  Infants who show early symptoms often die in early childhood. Children who show later onset typically have milder symptoms can live into adulthood.  Adult height usually ranges from three to five feet.  Other symptoms may include heart and lung disease, stroke, excessive curvature of the spine, small or unusually shaped teeth, and darkened patches of skin on the back and neck.  Currently there is no cure for this condition and lifelong medical care is needed. Treatment is based on the symptoms and may include medications to prevent or treat infections and dialysis or a kidney transplant for kidney failure. 

What causes Schimke Immunoosseous Dysplasia?

Schimke Immunoosseous Dysplasia is caused by a gene change, or mutation, in both copies of the SMARCAL1 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. 

Segawa Syndrome, TH-Related

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What is Segawa Syndrome, TH-Related?

Segawa Syndrome, TH-Related (one form of Tyrosine Hydroxylase [TH] Deficiency) is an autosomal recessive disorder that affects the brain and nervous system. Signs and symptoms usually begin in infancy or early childhood and include coordination problems, tremor, developmental delays, stiff muscles, abnormal body positioning, drooping eyelids (ptosis), and involuntary jerking movements. Other health problems include constipation, gastroesophageal reflux, and problems maintaining normal blood sugar, body temperature, and blood pressure. Some children have more a more severe form of the disorder with intellectual disability and psychiatric disorders. Currently, there is no cure for this condition, although, for some people, treatment with L-Dopa may help reduce the symptoms.

Rarely, specific mutations in the same gene cause less severe form of Tyrosine Hydroxylase Deficiency, TH-Related called Dopa-Responsive Dystonia. Signs and symptoms range from mild to moderate and usually start in childhood with involuntary spasms of the legs, later progressing to the arms and then the rest of the body. Abnormal movements, coordination problems, and sleep disturbance are common. Intellect is not affected. Over time, if Dopa-Responsive Dystonia is not treated, tremor and abnormal repetitive movements similar to those seen in Parkinson disease occur. Treatment with L-Dopa is effective in preventing or reversing the symptoms.

What causes Segawa Syndrome, TH-Related?

Segawa Syndrome, TH-Related is caused by a gene change, or mutation, in both copies of the TH gene pair. These mutations cause the genes to not work properly or not work at all. The TH genes are important for the normal function of the nervous system. When both copies of the TH gene pair do not work properly, it leads to the symptoms described above. 

Severe Combined Immunodeficiency, ADA-Related

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What is Severe Combined Immunodeficiency, ADA-Related?

Severe Combined Immunodeficiency (SCID) refers to a group of inherited disorders of the immune system. Severe Combined Immunodeficiency, ADA-Related (also called Adenosine Deaminase Deficiency) is an autosomal recessive form of SCID in which the body cannot fight infections caused by bacteria, viruses, and fungi. Signs and symptoms of Severe Combined Immunodeficiency, ADA-Related usually start between six months and one year of age and include repeated long-lasting infections that can be life-threatening, poor growth, diarrhea, and itchy skin rashes. Occasionally, children with this condition have abnormalities of the ribs, liver, and nervous system and may have hearing loss. Without treatment, most children die before the age of two. Some children do not show symptoms until after one year of age and have fewer infections that are less severe. Treatment includes medications to treat the infections and increase immune system function. In some cases, affected individuals have been treated with stem cell transplantation from cord blood or bone marrow. Couples at risk of having an affected child may consider cord blood banking, as siblings have a higher chance of being a match for stem cell transplantation than a non-related individual.

What causes Severe Combined Immunodeficiency, ADA-Related?

Severe Combined Immunodeficiency, ADA-Related is caused by a change, or mutation, in both copies of the ADA 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.

Severe Combined Immunodeficiency, Type Athabaskan

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What is Severe Combined Immunodeficiency, Type Athabaskan?

Severe Combined Immunodeficiency (SCID) refers to a group of inherited disorders of the immune system. Severe Combined Immunodeficiency, Type Athabaskan is an autosomal recessive form of SCID that occurs more often in the Athabaskan-speaking Native American population.  Signs and symptoms of Severe Combined Immunodeficiency, Type Athabaskan usually start between three and six months of age and include chronic infections and sensitivity to ionizing radiation (the type found in X-rays).  Children with Severe Combined Immunodeficiency, Type Athabaskan have immune systems that cannot fight off infections.  They typically have repeated infections that are hard to treat and can be life-threatening.  Infants with this condition may have chronic diarrhea, skin rashes, and slow growth. Without treatment, the condition can be fatal. Treatment includes medications to treat the infections and increase immune system function. In some cases, affected individuals have been treated with stem cell transplantation from cord blood or bone marrow. Couples at risk of having an affected child may consider cord blood banking, as siblings have a higher chance of being a match for stem cell transplantation than a non-related individual.

Rarely, mutations in the same pair of genes that cause Severe Combined Immunodeficiency, Type Athabaskan instead cause a related type of SCID called Omenn Syndrome.  Symptoms of Omenn Syndrome are similar to Severe Combined Immunodeficiency, Type Athabaskan, but also include severe reddened and peeling skin and enlarged liver and spleen. 

What causes Severe Combined Immunodeficiency, Type Athabaskan?

Severe Combined Immunodeficiency, Type Athabaskan is caused by a change, or mutation, in both copies of the DCLRE1C 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.

Severe Combined Immunodeficiency, X-Linked

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What is Severe Combined Immunodeficiency, X-Linked (XSCID)?

Severe Combined Immunodeficiency, X-Linked (XSCID) is an X-linked inherited disorder of the immune system that affects males more often than females. Signs and symptoms in affected males begin in infancy.  Frequent bacterial, viral or fungal infections that do not respond well to treatment are common. These infections can cause life-threatening problems. Boys with XSCID also have failure to grow at the normal rate, absent tonsils and lymph nodes, gastrointestinal malabsorption (failure of the GI tract to absorb certain nutrients from food) and short stature. Treatment typically includes medications to treat infection and increase immune system function. In many cases, affected individuals have been treated with stem cell transplantation from cord blood or bone marrow. Couples at risk of having an affected child may consider cord blood banking, as siblings have a higher chance of being a match for stem cell transplantation than a non-related individual.

What causes Severe Combined Immunodeficiency, X-Linked (XSCID)?

Severe Combined Immunodeficiency, X-Linked (XSCID) is caused by a change, or mutation, in the IL2RG gene. This mutation 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 the symptoms described above.

Sjogren-Larsson Syndrome

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What is Sjögren-Larsson Syndrome?

Sjögren-Larsson Syndrome is an autosomal recessive disorder that causes dry, rough, scaly, itchy skin (ichthyosis) along with brain, nerve, and eye problems.  The severity and type of symptoms vary from person to person.  Most children with this condition are born with the skin problems, have delays in motor skills such as crawling and walking because of abnormal stiffness in the legs and arms (spasticity), have some degree of intellectual disability ranging from mild to severe, and often have speech delays with problems forming words.  Many people with Sjögren-Larsson Syndrome need help in walking and some need the use of a wheelchair.  Some affected individuals also have seizures, nearsightedness, and increased sensitivity to light (photophobia).  Currently there is no cure for this condition and treatment is based on the symptoms. 

 What causes Sjögren-Larsson Syndrome?

Sjögren-Larsson Syndrome is caused by a gene change, or mutation, in both copies of the ALDH3A2 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.

Smith-Lemli-Opitz Syndrome

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What is Smith-Lemli-Opitz Syndrome?

Smith-Lemli-Opitz Syndrome is an autosomal recessive disorder that causes slow growth, small head size, moderate-to-severe intellectual disability, heart defects, cleft palate (opening at the roof of the mouth) and other birth defects. Lifespan in children with Smith-Lemli-Opitz Syndrome is shortened and death occurs before age 2 in up to a third of affected children.  Currently there is no cure for this condition and treatment is based on symptoms.

What causes Smith-Lemli-Opitz Syndrome?

Smith-Lemli-Opitz Syndrome is caused by a gene change, or mutation, in both copies of the DHCR7 gene pair.  These mutations cause the genes to not work properly or not work at all. The function of the DHCR7 genes is to help produce cholesterol.  When there are mutations in both copies of the DHCR7 gene, body cells do not make enough cholesterol and toxic chemicals build up in the blood, nervous system, and other tissues and cause the symptoms described above. Increasing dietary cholesterol cannot cure Smith-Lemli-Opitz Syndrome and has not been proven to be helpful in improving symptoms. 

Spinal Muscular Atrophy

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What is Spinal Muscular Atrophy?            

Spinal Muscular Atrophy, also called SMA, is a serious autosomal recessive disorder that typically begins in infancy or childhood and causes worsening muscle weakness, decreased ability to breathe, and loss of motor skills. Most children with Spinal Muscular Atrophy have one of the early-onset forms with symptoms that begin in infancy, with death often occurring before the age of two. Some children have juvenile-onset SMA and develop muscle weakness and other symptoms later in childhood. In rare cases, symptoms do not begin until early adulthood, are less severe, and do not affect lifespan.  Currently there is no cure for Spinal Muscular Atrophy, although treatments are available that may lessen some of the symptoms in some patients.

What causes Spinal Muscular Atrophy?

Spinal Muscular Atrophy is caused by a change, or mutation, in both copies of the SMN1 gene pair.  These mutations, which often delete part or all of these genes, cause the genes to work improperly or not work at all.  When both copies of the SMN1 gene are missing or do not work correctly, it leads to the symptoms described above. 

Spondylothoracic Dysostosis, MESP2-Related

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What is Spondylothoracic Dysostosis, MESP2-Related?

Spondylothoracic Dysostosis, MESP2-Related (also known as Jarcho-Levin Syndrome) is an autosomal recessive disorder that causes abnormal growth of the spine and rib bones. Infants with Spondylothoracic Dysostosis, MESP2-Related are often born with a small chest and small fused ribs that do not expand well, which can lead to life-threatening breathing problems. Other signs and symptoms include a short stiff neck, abnormally formed vertebrae causing a shortened spine and trunk, scoliosis, and inguinal and umbilical hernias. Intelligence is not affected. Some babies are born with a similar but rare form of this disorder called Spondylocostal Dysostosis, MESP2-Related, which has the same bone abnormalities and other symptoms but the breathing problems are less severe and lower risk of death in infancy. There is no cure for either form of this disorder although careful medical treatment is important for infants with breathing problems and surgery may be needed for spine problems or hernias.

What causes Spondylothoracic Dysostosis, MESP2-Related?

Spondylothoracic Dysostosis, MESP2-Related is caused by a gene change, or mutation, in both copies of the MESP2 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.

Steroid-Resistant Nephrotic Syndrome

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What is Steroid-Resistant Nephrotic Syndrome?

Steroid-Resistant Nephrotic Syndrome is an autosomal recessive disorder that causes abnormal kidney function.  People with this condition have large amounts of protein in their urine, low amounts of albumin (a protein in the plasma of the blood), high levels of fat in the blood, and excess fluid in body tissues (edema).  Symptoms vary from person to person but usually start in childhood.  The kidney problems worsen over time, often leading to kidney failure in the teenage years or early adulthood.   Once kidney failure occurs, dialysis and then kidney transplantation are needed.  Currently there is no cure for this condition and treatment is based on symptoms.

What causes Steroid-Resistant Nephrotic Syndrome?

Steroid-Resistant Nephrotic Syndrome is caused by a gene change, or mutation, in both copies of the NPHS2 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.

Stuve-Wiedemann Syndrome

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What is Stuve-Wiedemann Syndrome?

Stuve-Wiedemann Syndrome is a rare autosomal recessive disorder that causes severe bone abnormalities.  Signs and symptoms are present at birth and include short stature, bowing of the long bones of the arms and legs (campomelia), and flexed fingers and toes (camptodactyly).  Babies with this condition have repeated episodes of severe fever (hyperthermia) and breathing problems that can be life-threatening. Infants with Stuve-Wiedemann Syndrome rarely survive. In those that do, scoliosis, bone fractures, joint abnormalities, bowing of limbs, and poor muscle tone (hypotonia) are common. Sleep apnea and feeding and swallowing problems can also occur. Currently there is no cure for this condition and treatment is based on the symptoms.

What causes Stuve-Wiedemann Syndrome?

Stuve-Wiedemann Syndrome is caused by a change, or mutation, in both copies of the LIFR 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.

Tay-Sachs Disease

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What is Tay-Sachs Disease?

Tay-Sachs Disease is an autosomal recessive disorder that affects the brain and nervous system with signs and symptoms usually starting in the first year of life.  Symptoms include muscle weakness, loss of motor skills such as turning over, sitting, and crawling. Over time, progressive brain damage, seizures, vision and hearing loss, intellectual disability, and paralysis occur. Death usually occurs in early childhood.  In rare cases, symptoms do not begin until early adulthood and progress slowly. In some cases, affected individuals have been treated with stem cell transplantation from cord blood or bone marrow. Couples at risk of having an affected child may consider cord blood banking, as siblings have a higher chance of being a match for stem cell transplantation than a non-related individual.

What causes Tay-Sachs Disease?

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

Tyrosinemia, Type 1

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What is Tyrosinemia, Type 1?

Tyrosinemia, Type 1 is an autosomal recessive disorder in which the body is unable to break down a building block of protein (amino acid) called tyrosine.  This condition causes a harmful buildup of tyrosine and other amino acids and toxins in the body leading serious health problems.  The signs and symptoms of untreated Tyrosinemia, Type 1 usually begin in infancy and include diarrhea, bloody stool, vomiting, swollen abdomen, poor weight gain, lethargy (tiredness), irritability, yellowing skin (jaundice), cabbage-like odor, bleeding problems, breathing trouble, and developmental delays.  If not treated, Liver and kidney failure as well as nervous system problems can occur.  

Babies with Tyrosinemia, Type 1 need lifelong dietary and medical treatments.  Early treatment can help prevent the liver, kidney, and brain problems.  Children who receive treatment early in life can often have healthy growth and development.

What causes Tyrosinemia, Type 1?

Tyrosinemia, Type 1 is caused by a gene change, or mutation, in both copies of the FAH gene pair. These mutations cause the genes to not work properly or not work at all. The function of the FAH genes is to breakdown tyrosine. When both copies of this gene do not work correctly, it can cause a buildup of toxic substances in the body which leads to the symptoms described above.

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