A rare autosomal recessive disorder in which skin and hair pigmentation is reduced, probably because of altered melanosome transport. There is also neurological impairment. In Griscelli's syndrome type 1 (GS1) there is a mutation in the myosin-5A gene, but there is no immunological impairment. GS2, caused by mutation in the RAB27A gene, the product of which is ras-related protein from megakaryocytes, is complicated by immune dysfunction. In GS3 there is hypomelanosis without immunologic or neurologic manifestations, which may be caused either by mutation in the gene for melanophilin or that for myosin-5A.
Subjects: Medicine and Health.