The foundation organizes study trips worldwide to various target countries, setting up cooperative arrangements with local universities or humanitarian groups, and then conducts door-to-door surveys with the people in the region, said MeiLani Hock, the foundation's director of public affairs.

Woodward said the samples tie to 6 million ancestors' pedigrees listed in the foundation's database, with collections currently running at 750 new samples each week worldwide.

"For every DNA sample, we also have the genealogical information that's associated with them," Woodward said.

Refining the tests

Bennett Greenspan is the president and chief executive officer of Houston-based Family Tree DNA. He, along with Sorenson, has been one of the front-runners in the industry of DNA and genealogical research.

Greenspan said for the greatest accuracy in DNA testing for genealogy, the DNA markers examined should be fast-changing or high-mutating, which enables scientists to more precisely analyze familial lines.

According to Fogg, Y-chromosome DNA is high-mutating and therefore more precise in its resolutions, whereas mitochondrial DNA has slower mutating chromosomes that men and women inherit from their mother. Only males have Y-chromosomes, and that DNA is inherited by men from their fathers.

Sorenson Genomics examines 43 markers for its Y-chromosome DNA testing. An exact match (43 of 43 markers) correlates to common paternal lineage from one to five generations, said Fogg. Fewer matches decrease the precision with which results can be measured.

"The question is, how refined can we get in our testing?" he said. Figuring 20 years per generation, Fogg said being able to track lineage within 100 years " is pretty significant."

Samples are typically collected by using cheek swabs or by using a mouthwash-type solution that is swirled around in the mouth for about 45 seconds.

Fogg said companies are competing to identify and expand the number of relevant genetic markers that can offer higher resolution and establish more accurate family genealogy. But, he added, "depending on which markers you're selecting, you may not be getting better results."

The foundation's Sorenson Genomics, through Sorenson's for-profit family networking company GeneTree, offers DNA testing using mitochondrial sampling, said GeneTree CEO James Lee Sorenson. The company plans to offer high-resolution Y-chromosome testing by this spring.

Sorenson Genomics also contracts with African Ancestry and the Provo-based Generations Network, which operates the popular Web site Ancestry.com.

Add historical research