WASHINGTON, April 13: Indigenous people around the world will be asked to supply a cheek swab to help geneticists answer the question of how humanity spread from Africa, the National Geographic Society and IBM said on Wednesday. They hope to sample 100,000 people or more and look for ancient clues buried in living DNA to calculate who came from where and when.

And for 100 dollars, anyone who wants to can supply his or her own cheek swab for a personalized analysis and perhaps to contribute to the research.

“We all came out of Africa, but how did we get to where we are today?” asked geneticist and anthropologist Spencer Wells.

“What we are aiming for is the story of everybody.”

Experts in related fields such as population genetics, archaeology, evolution science, linguistics and palaeontology will help in the five-year project.

Fossils provide some clues about where people settled as they evolved and moved from Africa to colonize every continent except Antarctica. But mysteries remain, for example, about how people first got to Australia 50,000 to 60,000 years ago, or when and from where the first humans arrived in the Americas.

Linguistics and DNA provide many clues, but the so-called Genographic Project will aim to systematically look at all peoples on all continents.

Teams in China, Russia, India, Lebanon, Brazil, South Africa, Paris, Britain and Australia have signed on to help.

The IBM will provide computers and technical equipment and the philanthropic Waitt Family Foundation, established by the founder of Gateway computers, will fund field research.

Some groups may be hostile to the effort, Wells said in a telephone interview. “There has been a history of exploitation of indigenous groups around the world,” he said.

Geneticists will look at little changes in DNA code that have been used by experts to trace human history. Mitochondrial DNA, handed down virtually unchanged from mothers to their children, is one source that was used to calculate the so-called ancestral Eve, who would have lived in Africa about 180,000 years ago.

Men have their own version, found in the Y chromosome, which is inherited with very little change from father to son. Tiny mistakes in the code that occur with each generation can be used as a kind of genetic clock to track backward.

People who buy the mail-in swab kit are unlikely to add to the indigenous people’s database, but can find out something about their own ancient ancestry and perhaps add to the effort, Wells said.—Reuters