You can now trace your family tree through DNA testing

They are everywhere these days — lurking at family reunions, popping up at funerals, trolling wedding receptions.
They don't want your blood, just your spit.
Geri Gibbons of Madison nabbed her 65-year-old uncle during his first trip to the U.S. from Scotland in September. Armed with a cotton swab, she swiped a swath of DNA-laden tissue from his mouth.

"I'm not entirely sure he knew what I was asking for," she says, "but he didn't seem to mind."
Gibbons shipped her uncle's cells to Family Tree DNA, one of about two dozen companies offering genetic ancestry tests. She has just started getting periodic e-mails back from the company alerting her to fellow test subjects who share her family's DNA markers, an indication of a relationship somewhere in time.
For Gibbons and other recreational genealogists, DNA testing unlocks exciting possibilities. Yet the newness of commercially available genetic tests and the quick growth of the industry has some people urging restraint.
In a Science magazine report in October, several scientists and scholars said the limitations of the tests make them less informative than many realize. Pilar Ossorio, an associate professor of law and bioethics at the University of Wisconsin Law School and a co-author of the Science article, said in an interview that she has strong privacy concerns because genetic genealogy companies are largely unregulated.
"Once your DNA gets out there, there are a lot of things that could happen to it — a lot of different kinds of tests and studies that could be done with it — and some of those might produce information that could come back to haunt you."
A new way to search
Gibbons, 45, has spent hundreds of dollars ordering birth certificates of potential ancestors in Europe, but the paper trail often fades prior to the 1850s. She spent about $200 for a 37-marker DNA package using her uncle's Y chromosome.
Test packages typically start with 12 markers and go as high as 67, with prices increasing accordingly. The more Y chromosome markers tested, the greater the ability to predict when two men shared a common ancestor.