Ancient DNA reveals the roots of traits in modern Europeans

A huge cache of ancient genomes spanning tens of thousands of years has revealed that many traits of modern Europeans had their roots elsewhere. Researchers identified characteristics brought by three main waves of human migration into the continent — hunter-gatherers from Asia around 45,000 years ago; farmers from the Middle East 11,000 years ago; and animal herders from the steppes of western Asia and eastern Europe 5,000 years ago. The latter brought genes for greater height and lighter skin to Northern Europe, as well as a heightened risk for multiple sclerosis. Northeastern Europeans, who tend to have the most hunter-gatherer ancestry, have variants that put them at higher risk of diabetes and Alzheimer’s disease.