How Mixed is the European Genome? VERY!

If you go back far enough, all people share a common ancestry. But some populations are more closely related than others based on events in the past that brought them together. Now, researchers reporting in the Cell Press journal Current Biology on September 17 have shown that it's possible to use DNA evidence as a means to reconstruct and date those significant past events. The findings suggest that evidence in our genomes can help to recover lost bits of history.

"We now have the statistical machinery to uncover which historical events have produced the mosaic genomes of people in Europe today," says George Busby of the University of Oxford. "The successful reconstruct ion of the genetic history of a region of the world that has been well investigated both archaeologically and historically suggests that these approaches have the potential to be applied to areas where history has not been so well recorded and where genetics might be the only way of recovering history."

Busby and his colleagues applied a new method they've developed to compare single genetic variants among populations, taking into account the relationships among those markers based on their physical proximity along the chromosomes. That information can be used to infer subtle relationships among populations, including those that are genetically very similar, as well as the history of a continent.

The new work shows that all European populations have mixed over time as people picked up and moved from one place to another. Usually this mixing has involved nearby groups, but sometimes populations bear the mark of invading populations from more distant locations.

pop sci link.

paper link.