Albinism

Albinism

Albinism (from Latin albus, meaning "white") is a lack of pigmentation in the eyes, skin and hair. Albinism is an inherited condition resulting from the combination of recessive alleles passed from both parents of an individual. This condition is known to affect mammals, fish, birds, reptiles, and amphibians.

While the most common term for an individual affected by albinism is "albino", some prefer "person with albinism", because "albino" is sometimes used in a derogatory way. The gene which results in albinism prevents the body from making the usual amounts of the pigment melanin.

Albinism used to be categorised as Tyrosinase positive or negative. In cases of Tyrosinase positive albinism, the enzyme tyrosinase is present but is unable to enter pigment cells to produce melanin. In tyrosinase negative cases, this enzyme is not produced. This classification has been rendered obsolete by recent research.

About 1 in 17,000 people have some type of albinism, although up to 1 in 75 are carriers.

There are many alterations of genes which are proven to be associated with albinism. All alterations, however, lead to an alteration of the melanin (pigment/coloring) production in the body. Melanin helps protect the skin from ultraviolet light coming from the sun (see human skin color for more information).

Organisms with albinism lack this protective pigment in their skin, and can burn easily from exposure to the sun as a result. Lack of melanin in the eye also results in problems with vision unrelated to photosensitivity.