Abstract

Vertebrate skin pigmentation is the phenotypic trait which is determined by a pigment, melanin; a biopolymer produced within epidermal melanocytes, packaged in specialized organelles called melanosomes by a process called melanogenesis. Eumelanin and pheomelanin are the two types of melanin formed within the melanocytes. The process of melanin production and its transfer to keratinocytes defines visible skin pigmentation. Various intrinsic factors including several genes involved in many signalling pathways such as SCF/KIT, neuregulin, endothelin, WNT, glutamatergic, adrenergic signalling pathways are involved in the process of melanogenesis. Along with the internal factors, some external factors including ultraviolet radiations, environmental pollutants and hormonal impregnation are also responsible for the increase of melanin synthesis. In the present chapter, we have discussed the biochemistry of the process of melanogenesis with a focus on a mechanism of melanin synthesis and the internal and external factors affecting melanogenesis.