Putting at-home DNA ancestry tests to the test

How accurate are DNA tests?
Posted at 7:57 PM, Mar 14, 2018

They are all the rage right now, they help you find your family's history. 

"We've always wondered about the validity of my dad's side of the family and their claims about where we're from."

Elizabeth Makos is as curious as we all are. 

"So we think we are half Italian, quarter Czechoslovakian and a quarter polish."

She agreed to help put these DNA tests, to the test. 

Makos gave saliva samples three times, one for Ancestry DNA, 23 and Me and MyHeritage. We sealed them up and sent them off and waited about 6 weeks.

We got her results back and here's what Makos thought of them.

"It's shocking. It is really shocking. I can't imagine what technology they employ to get these results," she said.

It's shocking because her results were all over the place. When it comes to Eastern Europe, Ancestry said she was 49 percent Eastern European, but 23 and me and MyHeritage only put the percentage in the high 20s. 

"When we look at it for example, it says the Balkans here… one says 34 percent and one says 18 percent. A bit of a discrepancy there."

Makos thought for sure she is 50 percent Italian. 23 and me and MyHeritage says she's closer to 30 percent. She even had some North African DNA.

"I would love to know," Makos said about having North African DNA. "I know I get really tan in the summer but I didn't know I got that tan… who knows."

The companies don't claim to be perfectly accurate, and use different algorithms. MyHeritage told us in a Skype interview, it maps more parts of the globe that other companies.

"MyHeritage DNA has 42 ethnic regions with percentages and that's the most on the market, Rafi Mendelsohn, spokesperson for MyHeritage said."

Mendelsohn encourages you to read the fine print including what companies might do with your DNA profile after testing.

"Personal information provided to MyHeritage is never sold, licensed or shared with any third parties, he said." 

Both Ancestry DNA and 23 and Me say your DNA could be used for medical research by its "partners" after your name has been stripped out. 

Peter Pitts, a former FDA associate commissioner said, watch out.

"Companies will tell you that they may sell the information but nobody can find you," Pitts said. "And that's not true. There's been studies done at Harvard for example where a couple of professors got genetic information that was supposedly anonymous and was able to figure out who the people were through very easy mechanisms."

He says the results shouldn't be taken as gospel and companies say don't use the findings to make medical decisions. 

"People need to understand that what they're getting back is an interesting snapshot not necessarily accurate or clinically relevant," Pitts said. 

Makos said she's telling her friends to use the tests only for fun.

"I'm glad we did this because I probably would have just taken one test on my own and completely trusted the results. This was very eye opening for sure."