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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

Usher Syndrome, Type 1B

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What is Usher Syndrome, Type 1B?

Usher Syndrome, Type 1B is autosomal recessive.  It is one of a group of inherited disorders that cause progressive hearing and vision loss.  In most cases of Usher Syndrome, Type 1B, severe hearing loss is present at birth and hearing aids are not usually helpful.  Balance is also affected, which leads to a delay in motor skills such as walking.  Retinitis Pigmentosa is an eye condition that occurs in most people with Usher Syndrome Type 1B and leads to damage to the retina, causing progressive loss of eyesight and eventual blindness.  Retinitis Pigmentosa with vision loss usually starts developing in childhood.  Usher Syndrome, Type 1B does not affect intelligence or life span.

The symptoms of Usher Syndrome, Type 1B vary from person to person and some people have less severe (moderate) hearing loss. Other people may have hearing loss only and do not develop Retinitis Pigmentosa.  Currently there is no cure for Usher Syndrome, Type 1B.

What causes Usher Syndrome, Type 1B?

Usher Syndrome, Type 1B is caused by a gene change, or mutation, in both copies of the MYO7A 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.

Usher Syndrome, Type 1C

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What is Usher Syndrome, Type 1C?

Usher Syndrome, Type 1C is autosomal recessive.   It is one of a group of inherited disorders that cause progressive hearing and vision loss.  In most cases of Usher Syndrome, Type 1C, severe hearing loss in both ears is present at birth and hearing aids are not usually helpful.  Balance is also affected, which leads to delays in motor skills such as walking.  Retinitis Pigmentosa is an eye condition that occurs in most people with Usher Syndrome, Type 1C and leads to damage to the retina, causing progressive loss of eyesight.  Retinitis Pigmentosa with vision loss often starts in the teenage years but sometimes not until adulthood.  Usher Syndrome, Type 1C does not affect intelligence or life span.

The symptoms of Usher Syndrome, Type 1C vary from person to person and some affected individuals have less severe (moderate) hearing loss. Others have hearing loss only and do not develop Retinitis Pigmentosa.  Currently there is no cure for Usher Syndrome, Type 1C.

What causes Usher Syndrome, Type 1C?

Usher Syndrome, Type 1C is caused by a gene change, or mutation, in both copies of the USH1C gene pair.  These mutations cause the gene 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.

Usher Syndrome, Type 1D

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What is Usher Syndrome, Type 1D?

Usher Syndrome, Type 1D is autosomal recessive.  It is one of a group of inherited disorders that cause progressive hearing and vision loss.  In most cases of Usher Syndrome, Type 1D, severe hearing loss is present at birth and hearing aids are not usually helpful.  Balance is also affected, which leads to a delay in motor skills such as walking.  Retinitis Pigmentosa is an eye condition that occurs in people with Usher Syndrome Type 1D and leads to damage to the retina, causing progressive loss of eyesight and eventual blindness.  Retinitis Pigmentosa with vision loss may start developing in childhood or not until adulthood.  Usher Syndrome, Type 1D does not affect intelligence or life span.

The symptoms of Usher Syndrome, Type 1D vary from person to person and some affected individuals have less severe (moderate) hearing loss. Others may have hearing loss only and do not develop Retinitis Pigmentosa.  Currently there is no cure for Usher Syndrome, Type 1D.

What causes Usher Syndrome, Type 1D?

Usher Syndrome, Type 1D is caused by a gene change, or mutation, in both copies of the CDH23 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.

Usher Syndrome, Type 1F

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What is Usher Syndrome, Type 1F?

Usher Syndrome, Type 1F is autosomal recessive.  It is one of a group of inherited disorders that cause progressive hearing and vision loss.  In most cases of Usher Syndrome, Type 1F, severe hearing loss is present at birth and hearing aids are not usually helpful.  Balance is also affected, which leads to a delay in motor skills such as walking.  Retinitis Pigmentosa is an eye condition that occurs in most people with Usher Syndrome Type 1F and leads to damage to the retina, causing progressive loss of eyesight and eventual blindness.  Retinitis Pigmentosa with vision loss typically starts developing in the teenage years or early adulthood.  Usher Syndrome, Type 1F does not affect intelligence or life span. 

The symptoms of Usher Syndrome, Type 1F vary from person to person and some people have less severe (moderate) hearing loss. Other people may have hearing loss only and do not develop Retinitis Pigmentosa.  Currently there is no cure for Usher Syndrome, Type 1F.

What causes Usher Syndrome, Type 1F?

Usher Syndrome, Type 1F is caused by a gene change, or mutation, in both copies of the PCDH15 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.

Usher Syndrome, Type 2A

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What is Usher Syndrome, Type 2A?

Usher Syndrome, Type 2A is autosomal recessive.  It is one of a group of inherited disorders that cause progressive hearing and vision loss.  In most cases of Usher Syndrome, Type 2A, moderate to severe hearing loss is present at birth and affects higher frequencies more than lower frequencies.  Speech involves lower frequencies, so speech and understanding language is often possible for children with this condition, although hearing aids and speech therapy are often needed.  Retinitis Pigmentosa is an eye condition that occurs in individuals with Usher Syndrome, Type 2A and leads to damage to the retina, causing progressive loss of eyesight.  Retinitis Pigmentosa with vision loss usually starts in the teenage years.  Usher Syndrome, Type 2A does not affect intelligence or life span. Some individuals with Usher Syndrome, Type 2A have Retinitis Pigmentosa only and do not have hearing loss. Currently there is no cure for this condition.

What causes Usher Syndrome, Type 2A?

Usher Syndrome, Type 2A is caused by a gene change, or mutation, in both copies of the USH2A 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.

Usher Syndrome, Type 3

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What is Usher Syndrome, Type 3?

Usher Syndrome, Type 3 is autosomal recessive.  It is one of a group of inherited disorders that cause progressive hearing and vision loss.  People with Usher Syndrome, Type 3 usually start losing their hearing in late childhood or the early teenage years and typically have profound deafness by adulthood.  Balance may also be affected, causing problems with walking and coordination. Retinitis Pigmentosa is an eye condition that occurs in most individuals with Usher Syndrome, Type 3 and leads to damage to the retina, causing progressive loss of eyesight starting in childhood or the teenage years.  Usher Syndrome, Type 3 does not affect intelligence or life span.

The symptoms of Usher Syndrome, Type 3 vary from person to person and some people have less severe hearing loss. Other people may have hearing loss only and do not develop Retinitis Pigmentosa.  Currently there is no cure for this Usher Syndrome, Type 3.

What causes Usher Syndrome, Type 3?

Usher Syndrome, Type 3 is caused by a gene change, or mutation, in both copies of the CLRN1 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.

Very Long-Chain Acyl-CoA Dehydrogenase Deficiency

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What is Very Long-Chain Acyl-CoA Dehydrogenase Deficiency?

Very Long-Chain Acyl-CoA Dehydrogenase Deficiency (VLCAD Deficiency) is an autosomal recessive disorder that prevents the body from breaking down certain fats to energy, particularly during periods of fasting, illness, or exercise.  Signs and symptoms can begin anytime between infancy and adulthood.  Infants with the most severe form of VLCAD Deficiency develop symptoms in the first few months of life.  VLCAD Deficiency causes a thickening of the heart muscle (cardiomyopathy) which causes the heart not to work properly.  It can also cause an abnormal heart rhythm and/or fluid around the heart.  Infants with VLCAD Deficiency can have poor muscle tone, lack of energy, an enlarged liver, and periods of low blood sugar (hypoglycemia).  If not treated, affected infants can die.  With early diagnosis and lifelong treatment, infants with VLCAD Deficiency can survive and may have healthy growth and development.

Affected individuals who develop symptoms in childhood may not have heart disease.  People with the childhood-onset form typically have low blood sugar, an enlarged liver, and muscle weakness, especially after exercise.  Most individuals with VLCAD Deficiency have signs and symptoms that do not begin until adulthood.  This milder form typically does not affect the heart and may or may not cause low blood sugar.  Individuals with VLCAD Deficiency that begins in adulthood can have muscle cramps and pain, often following exercise.  If untreated, the body breaks down muscles and kidney damage can occur.  With careful treatment, people with the childhood and adult forms of VLCAD Deficiency can live healthy lives with typical growth and development.

What causes Very Long-Chain Acyl-CoA Dehydrogenase Deficiency?

VLCAD Deficiency is caused by a gene change, or mutation, in both copies of the ACADVL gene pair.  These mutations cause the genes to not work properly or not work at all.  The function of the ACADVL genes is to help break down fat in the body so that it can be used for energy.  When both copies of this gene do not work correctly, the body cannot break down fats which build up and cause the symptoms described above.

Walker-Warburg Syndrome, FKTN-Related

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What is Walker-Warburg Syndrome, FTKN-Related?

Walker-Warburg Syndrome, FTKN-Related is an autosomal recessive disorder that affects many parts of the body, especially the brain, eyes, and muscles. Signs and symptoms are often present before birth but sometimes start in infancy and include weak muscle tone (hypotonia), excess fluid on the brain (hydrocephalus), severe brain abnormalities, and eye defects with vision problems. Infants and children with Walker-Warburg Syndrome, FTKN-Related have worsening muscle weakness, problems with movement and coordination, seizures, and severe developmental delay with intellectual disability. Although symptoms vary from person to person, lifespan is usually shortened with death often occurring in early childhood. There is no cure or specific treatment for this disorder.

Rarely, mutations in the same pair of genes cause either a related condition called Fukuyama Congenital Muscular Dystrophy, a milder condition called Limb-Girdle Muscular Dystrophy, Type 2M, or, very rarely, Dilated Cardiomyopathy, Type 1X. Fukuyama Congenital Muscular Dystrophy causes brain and eye abnormalities and severe muscle weakness and is found mainly in people of Japanese ancestry. Limb-Girdle Muscular Dystrophy, Type 2M causes progressive weakness in the muscles of the arms, legs, shoulders, and hips but does not affect the brain. Symptoms of Dilated Cardiomyopathy, Type 1X include an enlarged and weakened heart and sometimes muscle weakness, usually beginning in adulthood.

What causes Walker-Warburg Syndrome, FTKN-Related?

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

Wilson Disease

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What is Wilson Disease?

Wilson Disease is an autosomal recessive disorder that causes copper from the diet to build up in certain parts of the body, especially the liver, eyes, and brain. Signs and symptoms of Wilson Disease usually begin in the teenage years and in rare cases not until adulthood.  Symptoms include liver disease, nervous system and psychiatric problems, and specific eye findings called Kayser-Fleischer rings (green/brown colored areas of excess copper on the surface of the eyes that do not interfere with vision). Other symptoms may include problems with coordination, movement, and behavior. Wilson Disease is commonly treated through chelation therapy to remove the excess stored copper from the body. This treatment helps to slow, and in some cases stop, the progression of the disease and improve symptoms.  With treatment, people with Wilson Disease can have a normal lifespan.

What causes Wilson Disease?

Wilson Disease is caused by a change, or mutation, in both copies of the ATP7B gene pair. These mutations cause the genes to not work properly or not work at all.  Normal function of the ATP7B genes is needed for normal transport of copper within the cells of the body. When both copies of the ATP7B gene do not work correctly, it leads to the symptoms described above.

Wolman Disease

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What is Wolman Disease?

Wolman Disease, a form of Lysosomal Acid Lipase Deficiency, is an autosomal recessive disorder in which the body is unable to break down and use cholesterol and fats from the diet.  Cholesterol and fats then build up in many organs of the body and lead to the disease symptoms. Signs and symptoms usually begin in infancy and include enlarged liver and spleen (hepatosplenomegaly), poor weight gain, poor muscle tone, yellowing of the skin and the whites of the eyes (jaundice), liver disease, anemia, vomiting, and diarrhea.  Infants with Wolman Disease also have developmental delays and are malnourished.  There is no cure for Wolman Disease and most affected children die in infancy or early childhood. 

A milder form of Lysosomal Acid Lipase Deficiency, called Cholesteryl Ester Storage Disease, has symptoms that vary from person to person and include buildup of cholesterol and fats in the body, enlarged liver with cirrhosis, hardening of the arteries (atherosclerosis), and an increased risk for heart disease and stroke.  Symptoms may start in early childhood or not until adulthood and lifespan may be decreased. 

What causes Wolman Disease?

Wolman Syndrome is caused by a gene change, or mutation, in both copies of the LIPA gene pair. These mutations cause the genes to not work properly or not work at all. The LIPA gene is important for the breakdown of cholesterol and triglycerides in the body. When both copies of the LIPA gene pair do not work properly, it leads to the symptoms described above. 

It is sometimes, but not always, possible to tell whether a specific gene mutation will cause Wolman Syndrome or Cholesteryl Ester Storage Disease. 

Zellweger Spectrum Disorders, PEX1-Related

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What is Zellweger Spectrum Disorders, PEX1-Related?

Zellweger Spectrum Disorders, PEX1-Related refers to a group of autosomal recessive conditions that includes Zellweger Syndrome, the most severe form; Infantile Refsum Disease (IRD) and Neonatal Adrenoleukodystrophy (NALD), intermediate in severity; and Heimler Syndrome, the mildest form.  Children born with Zellweger Spectrum Disorders, PEX1-Related can have signs and symptoms in the newborn period or not until later in childhood.  Signs and symptoms of Zellweger Syndrome, the most severe form, include low muscle tone (hypotonia), feeding problems, distinctive facial features, developmental delay, seizures, and liver disease.  Infants with Zellweger Syndrome often die in the first year of life.  Children with Infantile Refsum Disease or Neonatal Adrenoleukodystrophy often have longer survival with symptoms that include slowly progressing vision and hearing loss, intellectual disability, developmental delay, hypotonia, liver disease, and other medical problems.  Heimler Syndrome is a milder and very rare condition with symptoms that include sensorineural hearing loss, nail abnormalities, and loss of tooth enamel; intelligence is not affected.  Currently there is no cure for these disorders and treatment is based on symptoms.

What causes Zellweger Spectrum Disorders, PEX1-Related?

Zellweger Spectrum Disorders, PEX1-Related are caused by a gene change, or mutation, in both copies of the PEX1 gene pair.  These mutations cause the genes to not work properly or not work at all.  The normal function of the PEX1 gene pair is to help makes structures in our cells called peroxisomes that clear harmful substances from the body. When both copies of the PEX1 gene do not work correctly, peroxisomes do not form correctly in the cells of our body, leading to the symptoms described above.

Zellweger Spectrum Disorders, PEX10-Related

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What is Zellweger Spectrum Disorders, PEX10-Related?

Zellweger Spectrum Disorders, PEX10-Related refers to a group of autosomal recessive disorders that includes Zellweger Syndrome, the most severe form, along with Infantile Refsum Disease (IRD) and Neonatal Adrenoleukodystrophy (NALD) which are intermediate in severity. Children born with Zellweger Spectrum Disorders, PEX10-Related can have signs and symptoms in the newborn period or not until later in childhood.  Signs and symptoms in Zellweger Syndrome, the most severe form, include low muscle tone (hypotonia), feeding problems, distinctive facial features, developmental delay, seizures, and liver disease.  Infants with Zellweger Syndrome often die in the first year of life.  Children with Infantile Refsum Disease or Neonatal Adrenoleukodystrophy often have longer survival with symptoms that include slowly progressing vision and hearing loss, intellectual disability, developmental delay, hypotonia, liver disease, and other medical problems.  Currently there is no cure for these disorders and treatment is based on symptoms.

What causes Zellweger Spectrum Disorders, PEX10-Related?

Zellweger Spectrum Disorders, PEX10-Related are caused by a change, or mutation, in both copies of the PEX10 gene pair.  These mutations cause the genes to not work properly or not work at all.  The normal function of the PEX10 genes is to help make peroxisomes, structures in our cells that clear harmful substances from the body. When both copies of the PEX10 gene do not work correctly, peroxisomes do not form correctly, leading to the symptoms described above.

Zellweger Spectrum Disorders, PEX2-Related

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What is Zellweger Spectrum Disorders, PEX2-Related?

Zellweger Spectrum Disorders, PEX2-Related refers to a group of autosomal recessive disorders that includes Zellweger Syndrome, the most severe, along with Infantile Refsum Disease (IRD) and Neonatal Adrenoleukodystrophy (NALD) which are intermediate in severity. Children born with Zellweger Spectrum Disorders, PEX2-Related can have signs and symptoms in the newborn period or not until later in childhood.  Signs and symptoms in Zellweger Syndrome, the most severe form, include low muscle tone (hypotonia), feeding problems, distinctive facial features, developmental delay, seizures, and liver disease.  Infants with Zellweger Syndrome often die in the first year of life.  Children with Infantile Refsum Disease or Neonatal Adrenoleukodystrophy often have longer survival with symptoms that include slowly progressing vision and hearing loss, intellectual disability, developmental delay, hypotonia, liver disease, and other medical problems.  Currently there is no cure for these disorders and treatment is based on symptoms.

What causes Zellweger Spectrum Disorders, PEX2-Related?

Zellweger Spectrum Disorders, PEX2-Related are caused by a change, or mutation, in both copies of the PEX2 gene pair.  These mutations cause the genes to not work properly or not work at all.  The normal function of the PEX2 genes is to help make peroxisomes, structures in our cells that clear harmful substances from the body. When both copies of the PEX2 gene do not work correctly, peroxisomes do not form correctly, leading to the symptoms described above.

Zellweger Spectrum Disorders, PEX6-Related

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What is Zellweger Spectrum Disorders, PEX6-Related?

Zellweger Spectrum Disorders, PEX6-Related refers to a group of autosomal recessive conditions that includes Zellweger Syndrome, the most severe form; Infantile Refsum Disease (IRD) and Neonatal Adrenoleukodystrophy (NALD), intermediate in severity; and Heimler Syndrome, the mildest form.  Children born with Zellweger Spectrum Disorders, PEX6-Related can develop signs and symptoms in the newborn period or later in childhood.  Signs and symptoms in Zellweger Syndrome, the most severe form, include low muscle tone (hypotonia), feeding problems, distinctive facial features, developmental delay, seizures, and liver disease.  Infants with Zellweger Syndrome often die in the first year of life.  Children with Infantile Refsum Disease or Neonatal Adrenoleukodystrophy often have longer survival with symptoms that include slowly progressing vision and hearing loss, intellectual disability, developmental delay, hypotonia, liver disease, and other medical problems.  Heimler Syndrome is a milder and very rare condition with symptoms that include sensorineural hearing loss, nail abnormalities, and loss of tooth enamel; intelligence is not affected. Currently there is no cure for these disorders and treatment is based on symptoms.

What causes Zellweger Spectrum Disorders, PEX6-Related?

Zellweger Spectrum Disorders, PEX6-Related are caused by a change, or mutation, in both copies of the PEX6 gene pair.  These mutations cause the genes to not work properly or not work at all. The normal function of the PEX6 genes is to help make peroxisomes, structures in our cells that clear harmful substances from the body.  When both copies of the PEX6 gene do not work correctly, peroxisomes do not form correctly, leading to the symptoms described above.

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