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OCA2 (tyrosinase-positive albinism) is the most common form of generalized albinism characterized at birth by the presence of a certain amount of pigment in the skin and in the eyes of patients who continue to produce it and accumulate it throughout life. The skin is white, does not show general pigmentation and does not tan with exposure to the sun.
As for OCA1, there is a possibility for the development of pigmented lesions of the skin (freckles and lentigo), often on sun-exposed areas, but usually does not result in a tan.
The hair can be very weakly pigmented, taking on a yellow or light blonde, or with more pigments, strong blonde, golden blonde or even red.
The iris is blue-grey, sometimes slightly pigmented, the degree of transparency, visible with transillumination, depends on the amount of pigment present.
OCA2 is the product of a mutation of the human P gene, which was mapped on chromosome 15q11-12 that codes for the protein P responsible of the tyrosine's protein across the membrane of the melanosome. Tyrosine activity is normal.
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