Map showing the distribution of the Khoisan languages (yellow)
The most comprehensive look at the genome of Africans is published in the journal Cell today. The paper titled, “Evolutionary History and Adaptation from High-Coverage Whole-Genome Sequences of Diverse African Hunter-Gatherers,” focused on three hunter-gatherer populations; Pygmies from Cameroon and two groups from Tanzania, the Khoesan-speaking Hadza and Sandawe. The publication covered each of the genomes of five individuals from these groups over 60 times. The paper ultimately outlines some interesting findings, such as a new understanding on the extent of genetic diversity, and mysterious admixture.
We already have known that genetic diversity of people in Africa is greater than anywhere else on Earth. This knowledge plays into the concept of the the founder effect), where as we sample populations out of Africa, along the paths of migration of early Homo sapiens, we find that human populations tend to become more and more genetically similar the farther from the continent we go.
But just how diverse are some of the oldest living populations within Africa?
The authors discovered over 3.4 million genetic variants, or SNPs, of which a staggering 5-million of these variants are novel to us. Some of the loci give insight into adaptive changes in immunity, metabolism, olfactory and taste perception, reproduction, and wound healing. Interestingly, the Pygmy population, has multiple highly differentiated loci on genes on chromosome 3 which function in growth and anterior pituitary function and are associated with height.
Source and full article: Anthropology.net.
