As recently as 2008, scientists thought that Neanderthals and modern humans had never mated. Then, last year, they said that the two species had, but that the few Neanderthal genes that survived in modern human DNA were not functional. Now researchers believe that key versions of immune system genes in modern humans appear to have been passed down by archaic relatives, including Neanderthals after all, reports the L.A. Times.
What’s the Big Idea?
DNA inherited from Neanderthals and newly discovered hominids dubbed the Denisovans has contributed to key types of immune genes still present among populations in Europe, Asia, and Oceania. And scientists speculate that these gene variants must have been highly beneficial to modern humans, helping them thrive as they migrated throughout the world. These ancient HLA genes are still protecting us today. For example, the archaic HLA-A*11 variant now common in modern Asia provides immunity against some strains of Epstein Barr virus.