Abstract
Inherited diseases of pigmentation were among the first traits studied in humans because of their easy recognition. This article presents selected hypopigmentary disorders, which can be divided into hypomelanocytoses and hypomelanoses. Hereditary hypomelanoses are caused by abnormal melanin biosynthesis as well as by abnormal transfer of mature melanosomes to melanocyte dendrites and to neighboring cells. These disorders are represented by oculocutaneous albinism, Hermansky-Pudlak syndrome, Chediak-Higashi syndrome, Griscelli syndrome, Menkes syndrome and phenylketonuria, and are caused by different mutations of the following genes: TYR, P, TRP1, MATP, HPS, CHS, MYO5A, RAB27A, MLPH, ATP7A and PAH. Oculocutaneous albinism is caused by a deficiency of melanin pigment in the skin, hair, and eye and results from mutations in the TYR, P, TRP1 and MATP genes involved in the biosynthesis of melanin pigment. Mutations in the HPS, CHS, MYO5A, RAB27A and MLPH genes, which regulate the biogenesis, maturation and transfer of me-lanosomes to neighboring cells, are responsible for such disorders as Hermansky-Pudlak, Chediak-Higashi and Griscelli syndromes. In turn, mutations of the ATP7A and PAH genes, regulating intracellular copper concentration and activity of phenylalanine hydroxylase, lead to Menkes syndrome and phenylketonuria.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have