For centuries, scientists have sought a biological method for tracing a person's geographic origin. Now, a group of researchers has developed such a genetic ancestry test that can pinpoint the location where a person's ancestors originated more than 1,000 years ago.
The genetic algorithm accurately predicts the country of ancestral origin for about 80 percent of people, and for isolated island populations, it can predict people's island or even village of origin in some cases, researchers report today (April 29) in a study published in the journal Nature Communications.
A person's DNA contains more than simple instructions — it also tells the story of their evolution, migrations, interbreeding and mixing, said study leader Eran Elhaik, a population geneticist at the University of Sheffield in England. (The Best Genealogy Software for Tracing Your Family Tree)
"Only genetic tools can access this vast archive and extract the exact information about our geographic origin," Elhaik told Live Science.
Researchers have been attempting to use genetic data to trace human origins for decades. The best efforts have been able to accurately trace ancestral place of origin within about 435 miles (700 kilometers) in Europe, but not very accurately in other countries.
Elhaik and his team created an algorithm that uses genetics to home in on an individual's country of origin, called the Geographic Population Structure, with the fitting acronym GPS. The method first reconstructs ancestral human gene pools around the world. Then, it analyzes an individual's genome and associates each "letter," or base, in the genetic code with one of the global gene pools, creating a kind of genetic fingerprint. Finally, it matches each fingerprint to the fingerprints of populations that have resided in a specific location for a long time.
The researchers used the GPS algorithm to trace the origins of more than 600 people worldwide. The algorithm matched 83 percent of those people to their ancestral country of origin, dating between 1,000 to 3,000 years ago.