A paper published online in Science last month has implications for understanding the biology of skin color, according to Greg Barsh, MD, PhD, a faculty investigator and faculty chair at HudsonAlpha Institute for Biotechnology. Barsh told Science magazine the new research is “really a landmark study of skin color diversity.” The HudsonAlpha researcher also authored a perspective paper about the new study – appearing in the November 17 issue of Science – with Hua Tang, PhD, of Stanford University.
“The remarkable genetic diversity within African populations is both a signature and a storybook of human origins,” Barsh and Tang write in their article. The new skin pigmentation research adds much-needed diversity to study of the complex genetics underlying skin color, they say. And, as the two geneticists point out, “As in all things, diversity matters.”
The new skin color study demonstrates the potential insights that can come from examining skin color variation across different geographic locations and ethnic groups. It looked at genes in 2000 African individuals ranging from light-skinned San hunter-gatherer populations in southern Africa to dark-skinned pastoralist populations in eastern Africa. The authors used a genome-wide association study (GWAS) to identify regions of the genome that contribute to skin color variation, and they carried out a series of analyses to pinpoint the genes responsible for skin pigmentation.
According to the online article announcing the publication:
Most people associate Africans with dark skin. But different groups of people in Africa have almost every skin color on the planet, from deepest black in the Dinka of South Sudan to beige in the San of South Africa. Now, researchers have discovered a handful of new gene variants responsible for this palette of tones.
The study, published online this week in Science, traces the evolution of these genes and how they traveled around the world. While the dark skin of some Pacific Islanders can be traced to Africa, gene variants from Eurasia also seem to have made their way back to Africa. And surprisingly, some of the mutations responsible for lighter skin in Europeans turn out to have an ancient African origin.