Ancestry Uses a Drop of Saliva to Find Your Relatives From Centuries Ago

By submitting a sample of your DNA, you can now learn about your ancestors from generations ago.

An Ancestry.com-owned company called AncestryDNA released a product this week that it claims can provide glimpses into the lives of your distant descendants.

In exchange for a drop of spit, about 30 percent of Ancestry's customers can access details about their probable long-lost relatives, including their hometown, their criminal record and potentially even their cause of death.

Previously, the  company has been offering a $99 DNA kit, which breaks down consumer's ethnicity and provides links to living relatives. But now the company is trying to go back several generations into the past. 

For the millions of people who are addicted to genealogical research, unlocking clues about family history is worthwhile in its own right.

But AncestryDNA says its new product could prove to be useful for those who want to learn more about their own health. If the data is accurate, it might indicate a family history of a disease like breast cancer.

“If you take the DNA test, there’s a decent chance you’ll learn something about your ancestors as far back as the eighteenth-century,” said Ancestry.com CEO Tim Sullivan.

“Family health histories are a natural extension of this product,” he added.

AncestryDNA is already testing a web service that lets people aggregate their family medical histories online, Sullivan said. But it’s not available to everyone just yet, as the company is slowly rolling out this tool to a small group.

The company is watching closely as DNA testing company 23andMe, based in Mountain View, pushes for regulatory approval from the U.S. Food and Drug Administration for its home DNA tests. AncestryDNA may release a similar service that determines people’s propensity for a whole battery of diseases.

Finding Your Roots

How is AncestryDNA tracing people’s family histories – no genealogical research required?

Its geneticists are making connections between living people, like second or third cousins, who have submitted their DNA samples. Once that happens, a new customer who hasn’t submitted any genealogical information can learn more about their "new" relative's family tree, and glean information pulled from death records and other sources.

Ancestry’s geneticists say this technique is effective enough to "retroactively" link people back to descendants who lived hundreds of years ago.

The company’s product manager, Kenny Freestone, demonstrated this week how it’s done.

Freestone's DNA sample connected him to a distant ancestor, a bearded fellow named Ebenezer Hunter, who was born in Scotland in 1831. Ancestry.com gathered information about Hunter from over 140 people’s family trees, as well as census records and other publicly available information.

Freestone discovered that his ancestor was a polygamist who sired 25 children; he also learned some basic facts about how he died.

Some genetics experts say products like these have enormous potential for health care.

“A couple of other labs have already tried to make these huge family trees using big databases,” said Alexandre Bolze, a geneticist and postdoctoral researcher at UCSF.

“This is useful to understanding how genetics influenced certain traits, like height. Not everything is caused by genetics.”

But others caution that it’s a challenge to determine if historical information is accurate.

“Going back three or four generations, it’s going to be hard for a researcher to know whether you are descended from George Smith, the oldest of the family, or any of the other sons,” said Hank Greely, a director at the Center for Law and Biosciences at Stanford University.

"The company is going to need an awful lot of family members' DNA to determine with a high degree of probability how closely you're related to a distant ancestor."

Greeley points out that it’s difficult for researchers to ascertain how long-lost relatives died, as reports are often inconclusive. Even 50 years ago, medical reports tended to be far more vague, citing things like “fever” or “cancer” as the cause of death.

It is worth informing your doctor if you learn that you have a family history of disease going back three or four generations, Greeley said, but it’s not cause for panic.

“It’s difficult to imagine that this information would be powerful enough to raise any immediate personal health concerns.”