DNA sequencing can already tell us a lot about our ancestors. But a new technique developed by an international team of scientists now allows them to pinpoint a person’s geographical origin — going back 1000 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 per cent success rate, compared to within about 800km 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 per cent of residents of 10 villages in Sardinia to their specific villages, and the other 75 per cent to within 50km. In 20 islands within Oceania, they could track 90 per cent 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-$200 if you have it done privately — you can uploads your DNA data to the GPS website to understand your ancestry. [Nature via Gizmag]