We’re more Neandertal than we thought

Modern people of European and Asian ancestry carry slightly more Neandertal DNA than previously realized.

About 1.8 to 2.6 percent of DNA in non-Africans is an heirloom of ancient human-Neandertal interbreeding, researchers report online October 5 in Science. That corresponds to 10 to 20 percent more Neandertal ancestry than previous estimates — and it may carry consequences for human health and behavior, say paleogeneticist Janet Kelso of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and colleagues. Analysis of DNA from an about 50,000-year-old Neandertal woman from Vindija Cave in Croatia allowed Kelso and colleagues to find the extra ancestry contribution. Among the gene variants modern humans inherited from Neandertals are ones associated with higher cholesterol, increased belly fat, rheumatoid arthritis and schizophrenia, researchers learned from analysis of the new Neandertal DNA.

An increased risk of sunburning as a child and a propensity to be an evening person may also be Neandertal legacies, Kelso and Max Planck colleague Michael Dannemann report in a separate study published October 5 in the American Journal of Human Genetics. Their analysis — which used DNA data from a Neandertal woman from the Altai Mountains in Siberia (SN: 1/25/14, p. 17) and 112,338 present-day British people — confirmed some links between Neandertal heritage and human diseases made by previous studies (SN: 3/5/16, p. 18), but didn’t find evidence that Neandertal gene variants contribute to obesity.