ALAD Porphyria is a rare genetic disorder caused by a deficiency of the enzyme ALAD (aminolevulinic acid dehydratase). This enzyme is responsible for the production of heme, a molecule that is essential for the production of hemoglobin, the protei...

Alagille Syndrome is a rare genetic disorder that affects the liver, heart, and other organs. It is caused by a mutation in the JAG1 gene, which is responsible for producing a protein that helps regulate the development of the liver, heart, and ot...

Alagille syndrome is a genetic disorder caused by a microdeletion of the short arm of chromosome 20 (20p12). It is characterized by a wide range of symptoms, including liver problems, heart defects, skeletal abnormalities, and facial features. It ...

Alagille syndrome is a genetic disorder caused by a mutation in the JAG1 gene. This gene is responsible for producing a protein that helps regulate the development of the heart, liver, and other organs. The mutation in the JAG1 gene results in a d...

No, Alagille syndrome is not due to a NOTCH2 point mutation. It is caused by mutations in the JAG1 or NOTCH2 genes....

Osteopetrosis may be inherited as either a dominant or recessive trait and is marked by increased bone density, brittle bones, and, in some cases, skeletal abnormalities. Although symptoms may not initially be apparent in people with mild forms of...

Albers-Schonberg osteopetrosis is a rare genetic disorder that affects the bones. It is characterized by abnormally dense bones that are prone to fractures and deformities. It is caused by a mutation in the gene that codes for the enzyme carbonic ...

The term albinism typically refers to oculocutaneous (ok-u-low-ku-TAY-nee-us) albinism (OCA) — a group of inherited disorders where there is little or no production of the pigment melanin. The type and amount of melanin your body produces de...

Albinism is a rare, non-contagious, genetically inherited condition that results in little or no production of the pigment melanin in the skin, hair, and eyes. People with albinism may have very pale skin, white or light-colored hair, and vision p...

Albinism-deafness syndrome is a rare genetic disorder that affects both hearing and pigmentation. People with this disorder have a lack of pigment in their skin, hair, and eyes, as well as hearing loss. The hearing loss is usually severe to profou...

A prolactinoma is a benign tumor of the pituitary gland (adenoma) that produces an excessive amount of the hormone prolactin. In women, hyperprolactinemia is characterized by irregular menstrual periods (amenorrhea), infertility and production of ...

Alcohol use disorder facts Alcohol abuse and dependence, now both included under the diagnosis of alcohol use disorder, is a disease that is characterized by the sufferer having a pattern of drinking excessively despite the negative ...

ALDH18A1-related De Barsy syndrome is a rare genetic disorder caused by mutations in the ALDH18A1 gene. It is characterized by a distinctive facial appearance, intellectual disability, growth delays, and vision and hearing problems. People with th...

Primary aldosteronism (al-DOS-tuh-ro-niz-um) is a type of hormonal disorder that leads to high blood pressure. Your adrenal glands produce a number of essential hormones. One of these is aldosterone, which balances sodium and potassium in your blo...

ALECT2 amyloidosis is a rare, inherited form of amyloidosis caused by a mutation in the ALECT2 gene. It is characterized by the buildup of abnormal proteins in the body's organs and tissues, leading to organ damage and other health problems. Sympt...