FREQUENT INTRAGENIC DELETION OF THE P-GENE IN TANZANIAN PATIENTS WITHTYPE-II OCULOCUTANEOUS ALBINISM (OCA2)

Type II oculocutaneous albinism (OCA2) is an autosomal recessive disor der in which the biosynthesis of melanin pigment is reduced in the ski n, hair, and eyes. OCA2, which results from mutations of the P gene, i s the most frequent type of albinism in African and African-American p atients. OCA2 is especially frequent in Tanzania, where it occurs with an incidence of similar to 1/1,400. We have identified abnormalities of the P gene in each of 13 unrelated patients with OCA2 from Tanzania . One of these, a deletion of exon 7, is strongly predominant, account ing for similar to 77% of mutant alleles in this group of patients.