[Principles of skin pigmentation. Biochemistry and regulation of melanogenesis].

Skin pigmentation is highly determined by genetic factors and so far more than 150 genes have been identified that affect skin color either directly or indirectly. The production of eu- and pheomelanin in melanosomes results from the complex interaction between melanogenic regulators in melanocytes and factors derived from keratinocytes and fibroblasts. Besides genetic determination, pigmentation depends on environmental and endocrine factors that modulate the amount, type and distribution of melanins in the skin. Understanding the intrinsic mechanisms of melanogenesis is the basis for modifications of skin pigmentation which are of great interest pharmaceutically and cosmeceutically.