Got Allergies? Blame Neanderthals

Humans can thank their Neanderthal ancestors for giving them the genes that fight diseases, but also for their allergies, new research suggests.

Genetic variants found in modern humans that originally came from Neanderthals may predispose the human immune system to overreact to environmental allergens, according to two new studies published today (Jan. 7) in the American Journal of Human Genetics.

But these Neanderthal loaner genes may have had a silver lining. The studies also found that interbreeding with Neanderthals may have helped ancient humans, who came from Africa, get a head start in settling Europe. Neanderthals, for example, had lived in Europe and western Asia for around 200,000 years before the arrival of modern humans. They were likely well-adapted to the local climate, foods and pathogens," Janet Kelso of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, said in a statement. "By [Neanderthals] interbreeding with these archaic humans, we modern humans gained these advantageous adaptations."