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...

What is brain cancer? Brain cancer is a disease of the brain in which cancer cells (malignant cells) arise in the brain tissue. Cancer cells grow to form a mass of cancer tissue (tumor) that interferes with brain functions such as muscle c...

A brain tumor is a mass or growth of abnormal cells in your brain. Many different types of brain tumors exist. Some brain tumors are noncancerous (benign), and some brain tumors are cancerous (malignant). Brain tumors can begin in your bra...

A brain tumor is a mass or growth of abnormal cells in your brain. Many different types of brain tumors exist. Some brain tumors are noncancerous (benign), and some brain tumors are cancerous (malignant). Brain tumors can begin in your bra...

A brain tumor is a mass or growth of abnormal cells in your brain. Many different types of brain tumors exist. Some brain tumors are noncancerous (benign), and some brain tumors are cancerous (malignant). Brain tumors can begin in your bra...

Camurati-Engelmann disease is a rare genetic disorder characterized by progressive widening and malformation of the shafts of the long bones (diaphyseal dysplasia). Major symptoms may include bone pain, particularly in the legs; skeletal abnormali...

Cataracts are a clouding of the lens in the eye that affects vision. Most cataracts are related to aging. Symptoms may include blurry vision, poor night vision, sensitivity to light and glare, faded colors, halos around lights, and double vision i...

Camurati-Engelmann disease is a rare genetic disorder characterized by progressive widening and malformation of the shafts of the long bones (diaphyseal dysplasia). Major symptoms may include bone pain, particularly in the legs; skeletal abnormali...

Fuchs' Dystrophy is a type of corneal dystrophy, a disorder that affects the cornea, the clear outer layer of the eye. It is a slowly progressive disorder that usually affects both eyes. Symptoms include blurred vision, sensitivity to light, and d...

Hartnup disease is a rare metabolic disorder inherited as an autosomal recessive trait. It involves an inborn error of amino acid metabolism as well as niacin deficiency. Factors that may precipitate acute attacks of this disorder may include poor...

Von Hippel-Lindau syndrome (VHL) is an autosomal dominant genetic disorder characterized by the abnormal growth of blood vessels in certain parts of the body (angiomatosis). Very small blood vessels (capillaries) "knot" together to form benign gro...

Leukoedema is a benign condition that affects the mucous membranes inside the mouth, causing them to appear white or grayish in color. It is often mistaken for oral thrush or leukoplakia, but it is actually a harmless and temporary condition that ...

Lowe syndrome is characterized by vision problems including clouding of the lenses of the eyes (cataracts) that are present at birth, kidney problems that usually develop in the first year of life, and brain abnormalities that are associated with ...

Lowe syndrome is characterized by vision problems including clouding of the lenses of the eyes (cataracts) that are present at birth, kidney problems that usually develop in the first year of life, and brain abnormalities that are associated with ...

Lowe syndrome is characterized by vision problems including clouding of the lenses of the eyes (cataracts) that are present at birth, kidney problems that usually develop in the first year of life, and brain abnormalities that are associated with ...

Morquio syndrome (mucopolysaccharidosis type IV; MPS IV) is a mucopolysaccharide storage disease that exists in two forms (Morquio syndromes A and B) and occurs because of a deficiency of the enzymes N-acetyl-galactosamine-6-sulfatase and beta-gal...

Nystagmus is a condition in which the eyes make repetitive, uncontrolled movements. It can be caused by a variety of conditions, including inner ear problems, vision problems, and neurological disorders. Symptoms may include blurred vision, dizzin...

Oculocutaneous albinism (OCA) is a group of rare inherited disorders characterized by a reduced amount or complete lack of melanin pigment in the skin, hair, and eyes. These conditions are caused by mutations in specific genes that are necessary f...

Pleuropulmonary blastoma (PPB) is a rare childhood cancer occurring in the chest, specifically in the lungs or in the coverings of the lungs called "pleura". PPB occurs almost exclusively in children under the age of approximately 7-8 years and ra...

Retinitis Pigmentosa (RP) is a group of inherited eye diseases that cause progressive vision loss. It is caused by a genetic mutation that affects the light-sensitive cells in the retina, which are responsible for converting light into signals tha...

General DiscussionRubinstein-Taybi syndrome is a rare genetic multisystem disorder that affects many organ systems of the body. The group of findings (constellation) associated with this syndrome include growth retardation and delayed bon...

Treacher Collins syndrome (TCS) is a rare genetic disorder characterized by distinctive abnormalities of the head and face area resulting from underdevelopment (hypoplasia) of certain facial structures including the jaw, cheekbones and nearby stru...

General Discussion Chromosome 9, Trisomy Mosaic, also known as Trisomy 9 Mosaicism syndrome, is a rare chromosomal disorder in which the entire 9th chromosome appears three times (trisomy) rather than twice in some cells of the body. The...

Vitamin A deficiency is a condition that occurs when a person does not get enough vitamin A in their diet. It can lead to a variety of health problems, including night blindness, dry eyes, and an increased risk of infection. It is most common in d...

Von Hippel-Lindau syndrome (VHL) is an autosomal dominant genetic disorder characterized by the abnormal growth of blood vessels in certain parts of the body (angiomatosis). Very small blood vessels (capillaries) "knot" together to form benign gro...

Whipple disease is a rare disease resulting from bacterial infection that leads to inadequate absorption of nutrients (malabsorption) from the intestine. It is believed to result from infection with bacteria known as Tropheryma whippelii. The infe...