A new article published in Clinical, Cosmetic and Investigational Dermatology discussed that human skin demonstrates a striking variation in tone and color – evident among multiple demographic populations. Such characteristics are determined predominantly by the expression of the genes controlling the quantity and quality of melanin.

The authors stated that gene expressions can significantly alter due to the presence of small nucleotide polymorphism affecting various steps of the melanogenesis process and are generally linked to the lighter skin phenotypes. In addition, genetically determined, constitutive skin color is complemented by the facultative melanogenesis and tanning responses—with high levels of melanin and melanogenic factors broadly recognized to have a protective effect against the UVR-induced molecular damage in darker skin. Long-term sun exposure, together with a genetic makeup responsible for the ability to tan or the activity of constitutive melanogenic factors, triggers defects in pigmentation across all ethnic skin types.

This article also reported that sun exposure has well documented beneficial effects that manifest at both skin homeostasis and the systemic level—such as synthesis of vitamin D—which is thought to be less efficient in the presence of high levels of melanin or potentially linked to the polymorphism in genes responsible for skin darkening triggered by UVR. It was inferred that modulating the activities of melanogenic genes, with the focus on the markers specifically altered by polymorphism combined with differential requirements of sun exposure in ethnic skin types, could enhance the applications of already existing skin brightening factors and provide a novel approach toward improved skin tone and health in personalized skincare.

Source: Clinical, Cosmetic and Investigational Dermatology. 2020 Mar 9;13:215-232. doi: 10.2147/CCID.S245043.