melanin synthesis

Last reviewed 01/2018

Melanin synthesis begins in the liver where phenylalanine is converted to tyrosine by the action of phenylalanine hydroxylase. Tyrosine is then converted to DOPA by the action of tyrosinase enzymes within the melanocyte's melanosome. Two or more enzymatic steps then convert DOPA into the dark pigments that are mixed melanins.

Melanin synthesis can be prevented if one of the relevant enzymes is missing: lack of tyrosinases produce albinism.

The control of melanin synthesis is dependent on internal factors e.g. melanocyte stimulating hormone, and external factors e.g. ultraviolet radiation exposure.