Abruzzo-Erickson syndrome is a rare genetic disorder characterized by intellectual disability, seizures, and facial abnormalities. It is caused by a mutation in the ARX gene, which is responsible for the development of the brain and other organs. ...

Adams-Oliver syndrome (AOS) is an extremely rare inherited disorder characterized by defects of the scalp and abnormalities of the fingers, toes, arms, and/or legs. The physical abnormalities associated with this disorder vary greatly among affect...

Absence deformity of leg-cataract syndrome is a rare genetic disorder characterized by the absence of the lower leg bones, cataracts, and other eye abnormalities. It is caused by a mutation in the gene that codes for the protein filamin A. This di...

Absence of fingerprints-congenital milia syndrome is a rare genetic disorder characterized by the absence of fingerprints and the presence of milia, which are small white cysts on the skin. People with this disorder may also have other skin abnorm...

Absence of the innominate vein is a rare congenital anomaly in which the right brachiocephalic vein (innominate vein) is absent. This anomaly is usually asymptomatic and is usually discovered incidentally during imaging studies. Treatment is usual...

Absence of the pulmonary artery is a rare congenital heart defect in which the pulmonary artery, which carries deoxygenated blood from the right ventricle to the lungs, is missing or underdeveloped. This condition can lead to a variety of complica...

Absence of uterine body is a rare congenital malformation in which the uterus is completely absent. This condition is also known as uterine agenesis or Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome. It is usually diagnosed during adolescence whe...

Absent radius-anogenital anomalies syndrome is a rare genetic disorder characterized by the absence of the radius bone in the forearm, as well as malformations of the genitals and urinary tract. Other features of the disorder may include short sta...

Absent thumb-short stature-immunodeficiency syndrome (ATSIS) is a rare genetic disorder characterized by the absence of the thumb, short stature, and immunodeficiency. It is caused by a mutation in the gene encoding the transcription factor FOXP2....

Absent tibia-polydactyly-arachnoid cyst syndrome is a rare genetic disorder characterized by the absence of the tibia bone in the lower leg, extra fingers or toes (polydactyly), and the presence of an arachnoid cyst in the brain. It is caused by a...

Acanthocheilonemiasis is a rare parasitic infection caused by the nematode Acanthocheilonema perstans. It is spread by the bite of certain species of mosquitoes and is most commonly found in tropical and subtropical regions. Symptoms of the infect...

Neuroacanthocytosis is a general term for a group of rare progressive disorders characterized by the association of misshapen, spiny red blood cells (acanthocytosis) and neurological abnormalities, especially movement disorders. Chorea, which is c...

Acanthokeratolytic verrucous nevus is a rare skin disorder characterized by the presence of wart-like lesions on the skin. These lesions are usually found on the face, neck, and upper trunk and are composed of thickened, scaly skin. They may be pr...

Epidermolysis bullosa (EB) is a genetic skin disorder characterized clinically by blister formation from mechanical trauma. There are four main types with additional sub-types identified. There is a spectrum of severity, and within each type, one ...

Epidermolysis bullosa (EB) is a genetic skin disorder characterized clinically by blister formation from mechanical trauma. There are four main types with additional sub-types identified. There is a spectrum of severity, and within each type, one ...

Acanthosis nigricans is a skin condition characterized by dark, velvety patches of skin that typically appear in body folds and creases, such as the neck, armpits, and groin. It is most commonly associated with insulin resistance and obesity, but ...