Old and new immune genetic variation

The Khoe-San people of Africa are one of the most ancient lineages of humans and thus can be examined to identify both ancient and recent humanspecific genetic variation. Investigating the alleles of the killer cell immunoglobulin-like receptors and their human leukocyte antigen class I ligands, which are involved in the immune response, Hilton et al. found evidence of both old and new genetic variants. Because these genes can affect pregnancy, the identification of one recently evolved variant at relatively high frequencies suggests that it may have conferred a selective advantage.

PLOS Genet. 10.1371/journal. pgen.1005439 (2015).