カメルーンのバカピグミーにおける1型皮膚眼白皮症の初報告

Oculocutaneous albinism type 1 (OCA1) caused by pathogenic variants of the TYR gene is an autosomal recessive disorder of pigmentation characterized by reduced biosynthesis of melanin pigment in skin, hair, and eyes. We had the opportunity to examine five East Cameroon Baka rainforest hunter-gatherers (historically called "Pygmies") with albinism and belonging to three different families. Screening of known albinism genes revealed a homozygous missense variant in the TYR gene, NM_000372.5: c.1109T>C; p.Met370Thr. In addition, one patient was also hemizygous for a variant in GPR143, the gene involved in ocular albinism (OA1). Another patient was also heterozygous for the common African and Afro-American 2.7-kb deletion in the OCA2 gene indicating admixture of one parent with neighboring Nzimé Bantu-speaking farmers. This is the first report of the occurrence of OCA1 in African rainforest hunter-gatherers.