Fewer than 15 genes have been directly associated with skin pigmentation variation in humans, leading to its characterization as a relatively simple trait. However, by assembling a global survey of quantitative skin pigmentation phenotypes, we demonstrate that pigmentation is more complex than previously assumed with genetic architecture varying by latitude. We investigate polygenicity in the Khoe and the San, populations indigenous to southern Africa, who have considerably lighter skin than equatorial Africans. We demonstrate that skin pigmentation is highly heritable, but that known pigmentation loci explain only a small fraction of the variance. Rather, baseline skin pigmentation is a complex, polygenic trait in the KhoeSan. Despite this, we identify canonical and non-canonical skin pigmentation loci, including near SLC24A5, TYRP1, SMARCA2/VLDLR, and SNX13 using a genome-wide association approach complemented by targeted resequencing. By considering diverse, under-studied African populations, we show how the architecture of skin pigmentation can vary across humans subject to different local evolutionary pressures.
- Martin, A.R., Lin, M., Granka, J.M., Myrick, J.W., Liu, X., Sockell, A., Atkinson, E.G., Werely, C.J., Möller, M., Sandhu, M.S. and Kingsley, D.M. (2017). An Unexpectedly Complex Architecture for Skin Pigmentation in Africans. Biorxiv, -, 200139.
Peoples: Khoe and San people | Places: Southern Africa | Topics: SLC24A5, SMARCA2/VLDLR, SNX13, and TYRP1 | DNA Type: Autosomal DNA