Atypical Norrie disease due to Xp11.3 microdeletion is a rare genetic disorder caused by a deletion of a small piece of genetic material on the X chromosome. It is characterized by severe vision loss, intellectual disability, and hearing loss. It ...

Atypical pantothenate kinase-associated neurodegeneration (PKAN) is a rare, inherited neurological disorder caused by mutations in the PANK2 gene. It is characterized by progressive dystonia (involuntary muscle contractions) and other neurological...

Atypical papilloma of the choroid plexus is a rare, benign tumor that develops in the choroid plexus, a network of blood vessels and nerve fibers in the brain. It is usually found in the lateral ventricles, the two large cavities in the brain. Sym...

Atypical progressive supranuclear palsy (aPSP) is a rare neurological disorder that affects movement, balance, and other functions. It is a form of progressive supranuclear palsy (PSP), a group of disorders that cause problems with movement, balan...

Atypical teratoid rhabdoid tumor (AT/RT) is a rare, aggressive type of cancer that usually affects children under the age of three. It is a tumor of the central nervous system, most commonly found in the brain and spinal cord. AT/RT is a fast-grow...

Atypical Timothy syndrome is a rare genetic disorder that affects the heart, nervous system, and other parts of the body. It is caused by a mutation in the CACNA1C gene, which is responsible for the production of a protein that helps regulate the ...

Atypical Werner syndrome is a rare genetic disorder that is characterized by premature aging. It is caused by a mutation in the WRN gene, which is responsible for producing a protein that helps maintain the stability of chromosomes. Symptoms of At...

Audiogenic seizures are seizures that are triggered by sound. They are most commonly seen in certain breeds of dogs, such as Beagles, Dachshunds, and Cocker Spaniels. Symptoms of audiogenic seizures can include trembling, salivation, and loss of c...

Auditory neuropathy-optic atrophy syndrome (ANOS) is a rare genetic disorder that affects the auditory and visual systems. It is characterized by hearing loss, optic atrophy (degeneration of the optic nerve), and other neurological symptoms. The h...

Auditory Processing Disorder (APD) is a complex problem. The term is used by many people, in very different ways. There is research underway to help understand this disorder. There also is research to investigate therapies that will help individua...

Auricular abnormalities-cleft lip with or without cleft palate-ocular abnormalities syndrome is a rare genetic disorder characterized by malformations of the ears, cleft lip and/or cleft palate, and ocular abnormalities. It is caused by a mutation...

Auriculocondylar syndrome (ACS) is a rare genetic disorder characterized by malformations of the ears, jaw, and other facial features. It is caused by a mutation in the EFTUD2 gene. Symptoms may include small ears, a small lower jaw, a cleft palat...

Auriculoosteodysplasia is a rare genetic disorder characterized by malformations of the ears, bones, and teeth. It is caused by a mutation in the GJA1 gene, which is responsible for the production of connexin 43, a protein that helps cells communi...

Frey syndrome is a rare disorder that most often occurs as a result of surgery in the area near the parotid glands. The parotid glands are the largest salivary glands in the body located just below the ears on either side of the face. The main sym...

Autism spectrum disorder is a condition related to brain development that impacts how a person perceives and socializes with others, causing problems in social interaction and communication. The disorder also includes limited and repetitive patter...

Autism spectrum disorder is a condition related to brain development that impacts how a person perceives and socializes with others, causing problems in social interaction and communication. The disorder also includes limited and repetitive patter...

Autism spectrum disorder due to AUTS2 deficiency is a rare genetic disorder caused by a mutation in the AUTS2 gene. This mutation results in a deficiency of the AUTS2 protein, which is involved in the development of the brain and nervous system. S...