May 1, 2014
Genetic GPS Helps You Trace Ancestor’s Home From 1,000 Years Ago
Brett Smith for redOrbit.com - Your Universe Online
While previous genetic research efforts have been able to identify a person’s ancestral origins within around 430 miles, a new system devised at the University of Sheffield in the United Kingdom can zero in on a person’s origin down to a particular village or island.
According to a new report in the journal Nature Communications, the Sheffield researchers were able to develop a system called Geographic Population Structure (GPS) that is capable of geo-locating someone’s ancestral home from 1,000 years ago.
The study team said their breakthrough came when they could determine where the gene pools that produced someone's DNA were last mixed. They added that this development has enormous implications for life-saving personalized medicine, improving forensic science and for the study of communities whose ancestral roots are under debate, such as African Americans and Roma gypsies.
Genetic admixture takes place when folks from two or more formerly separated populations start interbreeding, according to the researchers. This leads to the development of new gene pools that represent a mixture of the originator gene pool.
"If we think of our world as being made up of different colors of soup – representing different populations - it is easy to visualize how genetic admixture occurs,” said study author Eran Elhaik, a population geneticist from the University of Sheffield. “If a population from the blue soup region mixes with a population from the red soup region their off-springs would appear as a purple soup.”
[ Watch the Video: Using GPS To Track DNA ]
"The more genetic admixture that takes place, the more different colors of soup are introduced which makes it increasingly difficult to locate your DNA's ancestry using traditional tools like Spatial Ancestry analysis (SPA) which has an accuracy level of less than 2 percent,” Elhaik continued.
"What we have discovered here at the University of Sheffield is a way to find not where you were born – as you have that information on your passport – but where your DNA was formed up to 1,000 years ago by modeling these admixture processes,” he concluded "What is remarkable is that, we can do this so accurately that we can locate the village where your ancestors lived hundreds and hundreds of years ago – until now this has never been possible."
To test their GPS tool, the study team evaluated DNA from 10 villages on the Mediterranean island of Sardinia as well as over 20 islands in Oceania. The study revealed that 25 percent of the residents in Sardinia could be linked directly to their home village and most of the rest within 31 miles of their village. For Oceania, almost 90 percent of participants could be traced to their island.
"This is a significant improvement compared to the alternative SPA tool that placed Oceanians in India," Elhaik said.
"This technique also means that we can no longer easily classify people's ethnic identities with one single label,” he continued. “It is impossible for any of us to tick one box on a form such as White British or African as we are much complex models with our own unique identities. The notion of races is simply not plausible."
"To help people find their roots, I developed a website that allows anyone who has had their DNA genotyped to upload their results and use GPS to find their ancestral home," Tatarinova said.