An amino acid called tyrosine is normally converted by the body to the pigment melanin . Albinism results when the body is unable to produce melanin because of one of several possible defects in the metabolism of tyrosine. It is the most severe form of the condition.
Affected people have white hair, colorless skin, red irises, and vision defects.
Albinism of just the eyes also occurs and may be associated with several inheritable disorders. Piebaldism, or partial albinism, is a condition associated with a patchy absence of pigment. This may occur as a white forelock of hair, or as depigmented spots on the forehead, elbows, knees, or other body areas. Genetic counseling may be of value to individuals with a family history of albinism or piebaldism. No testing is usually required.