Finding the genetic trail
Harvard Medical School researchers have used a new DNA analysis technique to track when and how much gene flow occurred from sub-Saharan Africa into populations in Europe and the Middle East, highlighting not only the complexity of human migrations, but also the power of using whole-genome analysis to understand humanity’s past. Previous studies estimated the initial modern human migration out of Africa into Europe occurred about 45,000 years ago and showed that additional mixing occurred since then involving Africa, Europe, and the Middle East. Details of that subsequent mixing have been missing, however. Researchers in the lab of Associate Professor of Genetics David Reich have quantified when and how much mixing occurred in those populations after the initial migration from Africa, using techniques that his laboratory first developed two years ago to understand the flow of genes in the ancestors of populations in modern India. The study, published in the journal PLoS Genetics,...