DNA Sequences Can Trace Your Ancestors to Within 30 Miles

DNA sequencing can already tell us a lot about our ancestors—but now, a new technique developed by an international team of scientists allows them to pinpoint a person's geographical origin—going back 1,000 years.


The Geographic Population Structure (GPS) tool—slightly confusing, admittedly—beats previous best attempts to tie location to DNA. It can track populations back to the islands or villages they descend from, with a 98 percent success rate, compared to within about 500 miles for old methods.

By studying admixture—which is where two previously separate populations begin to interbreed and create a new gene pool—the team are able to understand where and when changes to historic DNA took place. In fact, they use 100,000 DNA signatures which are typical to specific geographical regions, and then compare these to autosomal chromosomes of a person being tested. Talking to Gizmag, Dr. Eran Elhaik from the University of Sheffield explained:

"We were surprised by the simplicity and precision of this method. People in a given geographical area are more likely to have similar genetics. When they also have genetic traits typically found in other, distant regions, the geographical origin of those traits is generally the closest location where those traits can be found."

The research results, published in Nature Communications, are certainly impressive. In one test, the team could place 25 percent of residents of 10 villages in Sardinia to their specific villages, and the other 75 percent to within 31 miles. In 20 islands within Oceania, they could track 90 percent back to their exact island.

It's not just a neat party trick, though. The development should help us understand a patient's ancestry better than ever, which should help improve our und knowledge of susceptibility to certain genetic diseases. Perhaps best of all, anyone can use it: If you have your autosomal DNA genotyped—which costs $100-200if you have it done privately—you can uploads your DNA data to the GPS website to understand your ancestry. [Nature via Gizmag]



Either this paper or this write-up makes no sense. I, and most people, do not have an ancestral line that returns to a single location. Does it produce an average location from all of your ancestral DNA? It seems like it would be completely useless for anyone with ancestors from more than one continent.