Got questions about DNA testing? This expert has answers

DNA testing is widely available now, advertised on TV and online.

Still, people may have some basic questions. In the October/November issue of Family Tree Magazine, Diahan Southard, one of the nation's leading DNA experts, provides some answers.

  • Do you need only one kind of DNA test?

That would depend on your research goals, and certainly autosomal testing is the one everyone can take. But many family historians need to find a male for Y-DNA testing (available at in order to verify the male line and the surname and link with others with more information.

  • Can you get DNA from stamps or hair samples?

There are companies that offer this, but the results are not a given, and it's also expensive.

  • Can DNA tests pinpoint locations where my ancestors lived?

This myth is busted, as DNA is not geographically specific. The ethnicity results that every company offers are based on reference populations that can vary.

  • Are my results 99.9% accurate?

This depends on how you interpret "accurate." All DNA testing results match you with a list of real people, with your closest match (the one with the highest centimorgan number in autosomal matches) at the top. Since I have more than 80,000 matches on, they vary from very close to some so distant I will never figure out kinship. DNA would not show them as matches if you didn't have some DNA in common. Stick with your closest matches and see where they fit on your tree.

  • Can DNA tell me how I am related to someone?

If the person has also done DNA testing, a relationship will be shown. You also need to do regular family history research through records to know how someone is kin.

  • Can the government (or insurance companies) use my DNA against me?

This myth is "busted" in her article. The companies stress privacy.

For the full article, see

At, the free site where the world's records are digitized, use the catalog feature to search for your county of interest. The records available will be listed in a standardized format: court, land, probate, etc., despite how the locale refers to them.

Contact Kenneth H. Thomas Jr., P. O. Box 901, Decatur, GA 30031 or

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