Oculocutaneous albinism is a group of conditions that affect the color of (pigmentation) of the skin, hair, and eyes. Affected individuals typically have very fair skin and white or light-colored hair. Long-term sun exposure greatly increases the risk of skin damage and skin cancers, including an aggressive form of skin cancer called melanoma, in people with this condition.

Oculocutaneous albinism can result from variants (also known as mutations) in several genes, including TYR, OCA2, TYRP1, and SLC45A2. Variants in the TYR gene cause type 1, variants in the OCA2 gene cause type 2, variants in the TYRP1 gene cause type 3, and variants in the SLC45A2 gene cause type 4. Variants in additional genes likely underlie the other forms of this disorder. The genes associated with oculocutaneous albinism are involved in producing a pigment called melanin, which is the substance that gives skin, hair, and eyes their color. In the retina, melanin also plays a role in normal vision. Variants in any of these genes disrupt the ability of cells to make melanin, which reduces pigmentation in the skin, hair, and eyes. A lack of melanin in the retina leads to the vision problems characteristic of oculocutaneous albinism.

While the prevalence of oculocutaneous albinism varies by type and country, it is estimated that this condition affects 1 in 4,000 to 7,000 people in African populations and 1 in 12,000 to 15,000 people in European populations. Some isolated communities have higher occurrences of oculocutaneous albinism than their neighboring areas. Prevalence information for other populations is difficult to estimate, but oculocutaneous albinism affects people in all regions of the world.

This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell must have a variant to cause the disorder. The parents of an individual with an autosomal recessive condition each carry one copy of the altered gene, but they typically do not show signs and symptoms of the condition.

Published Date: November 22, 2024
Published By: National Institutes of Health