Did your Ancestry.com DNA results change dramatically? Here's why

The company, which explores people's genealogical background through testing saliva samples, recently compared customers samples to 16,000 reference samples — previously, DNA had been compared to 3,000 results.

Some customers saw as much as a 10 to 20 per cent change to DNA results

Some Ancestry customers who have taken the DNA test, which involves spitting in a tube, may have noticed a dramatic change in their results. (Steve Berry/CBC)

When Katy Jean of Dartmouth, N.S., sent in a sample of her DNA to Ancestry.com a year ago, she was hoping the genealogy website would tell her more about her background and maybe fill in gaps on her family tree.

Once the results came in, Jean said she wasn't too surprised by the outcome — except for an unexplained one per cent result from Central Asia. 

But then things changed.

"There was a significant change in my DNA results," Jean said.

Jean went from having 75 per cent ancestry from Great Britain and 12 per cent Iberian Peninsula (Portugal & Spain) to 53 per cent England, Wales and Northwestern Europe, 31 per cent Ireland and Scotland. Iberian Peninsula and Central Asia disappeared.

The Ancestry results on the left are Katy Jean's old results, the results on the right are her latest results. (Submitted by Katy Jean)

What changed?

The reason for the change, according to Ancestry's website, is because the company has more DNA samples with which it can compare results.

When Ancestry first launched its DNA testing in 2012, it compared samples to 22 possible regions. Now the company can compare tests to 380 regions.

The company, which bills itself online as "the global leader in family history and consumer genomics," also added more reference samples, or DNA from people whose family have long-standing roots in a specific area. It now has 16,000 samples, up from 3,000. 

This, according to Ancestry's website, means new regions could appear while low-percentage regions — like Jean's Central Asia result — could disappear entirely. Some customers may not see any changes.

It's unclear how many customers saw dramatic changes to their results, which are taken from saliva samples.

Ancestry's chief science officer said she would provide more information Tuesday, but the company has released more details on the changes online.

"It's our most powerful way yet for you to better understand who and where you come from," said Barry Starr, director of scientific communication at Ancestry, in a video posted to YouTube last week.

Starr said Ancestry can now compare results to nine more regions in Asia, like Japan and the Philippines. What used to show up as Scandinavian in some results now lists Norway and Sweden separately. A Western Europe result is broken down into France or Germany.

Customers can still look at their previous results on their account for a limited time, Starr noted.

Some not so big changes

Bill Zebedee, also from Dartmouth, N.S., said his Ancestry test results changed, too — but they weren't as dramatic as Jean's.

"The only thing that got clarified was the region of England where the Zebedees come from, which is interesting, said Zebedee, who jokingly added that he's "beat the Zebedees research to death."

He said he was hoping to see more results from his mother's side, which is from Ukraine and Romania.

"There's not much DNA  coming from that right now and there's not many matches at all," he said.

The new results, Jean said, seem to be "way more accurate" now.

"It said that I had more Irish than the previous test. And I had known I had Irish ancestry. They only came over late 1800s early 1900s ... So I was kind of wondering why Ireland didn't show up before," Jean said.

Read more articles from CBC Nova Scotia

About the Author

Anjuli Patil

Reporter

Anjuli Patil is a reporter and occasional video journalist with CBC Nova Scotia's digital team.