Results can vary widely depending on which company you use


BY TINA HESMAN SAEY 2:41PM, JUNE 13, 2018

Commercials abound for DNA testing services that will help you learn where your ancestors came from or connect you with relatives. I’ve been interested in my family history for a long time. I knew basically where our roots were: the British Isles, Germany and Hungary. But the ads tempted me to dive deeper.

Previous experience taught me that different genetic testing companies can yield different results (SN: 5/26/18, p. 28). And I knew that a company can match people only to relatives in its customer base, so if I wanted to find as many relatives as possible, I would need to use multiple companies. I sent my DNA to Living DNA, Family Tree DNA, 23andMe and AncestryDNA. I also bought the National Geographic Geno 2.0 app through the company Helix. Helix read, or sequenced, my DNA, then sent the data to National Geographic to analyze.

These companies analyze hundreds of thousands of natural DNA spelling variations called single nucleotide polymorphisms, or SNPs. To estimate ethnic makeup, a company compares your overall SNP pattern with those of people from around the world. SNP matches also help companies see who in their database you’re related to.

Some of the companies also analyze a person’s Y chromosome or mitochondrial DNA. Y chromosome DNA traces a man’s paternal line. In contrast, mitochondrial DNA traces maternal heritage, since people inherit mitochondria, which generate energy for cells, only from their mothers. Neither type of DNA changes that much over time, so those tests usually can’t tell you much about recent ancestors.

Once I sent in DNA samples, my Web-based results arrived in just a few weeks. But my user experience, and results, were quite different for each company.

National Geographic Geno 2.0

At $199.95, National Geographic’s test is the most expensive, yet the least useful. The results are generic, and the ethnicity categories are overly broad. My results say that 45 percent of my heritage came from people living in southwestern Europe 500 to 10,000 years ago. That doesn’t tell me much and doesn’t reflect what I know of my family history.

There’s no relative matching, though Geno 2.0 shows which historical “geniuses” may have shared your mitochondrial or Y chromosome DNA. I don’t know how National Geographic knows about the mitochondria of Petrarch, Copernicus or Abraham Lincoln. So I’m skeptical that I am actually related to those famous figures, even from the distance of 65,000 years, the last time we supposedly had an ancestor in common. The service also calculated the percentage of Neandertal ancestry that I carry. I take geeky pride that 1.5 percent of my DNA comes from Neandertals, topping the 1.3 percent average for Geno 2.0 customers.

Overall, Geno 2.0 has a nice presentation, but I learned more about my family history elsewhere. Since I bought the Geno 2.0 kit as an app through Helix, I don’t know if the kit purchased directly from National Geographic, which is processed by Family Tree DNA, would yield different results.

ENGLISH ANCESTRY Living DNA offers fine-scale ethnicity estimates for people of British or Irish descent (Saey’s results shown). The company is less certain about subregional estimates than it is about global estimates.

Another expensive test ($159) came from Living DNA. When I saw the company’s ad claiming to pinpoint exactly where in the British Isles a person’s genetic roots stem from, I decided to give it a go. The company highlights ethnicity on a world map, then lets you zoom in from the continent level. I found that 22.5 percent of my heritage came from Lincolnshire in east-central England. I haven’t yet traced any ancestors to Lincolnshire, but I did find through much genealogical sleuthing that one of my sixth-great-grandfathers came from Aberdeen, Scotland. Living DNA says that 3.1 percent of my DNA is from Aberdeenshire. Written narratives on the website provide a history of each reported region.

Using mitochondrial DNA and, if applicable, Y chromosome DNA, the company can trace your maternal and paternal lines back to human origins in Africa and show where and when your particular line probably branched off the original. My “motherline” probably arose in the Near East 19,000 to 26,000 years ago, Living DNA claims, and my ancestors were some of the first people to enter Europe. In February, the company announced that it would soon launch a relative-matching service for its customers. I’m not sure the service would be worth the price tag for people whose ancestry doesn’t contain a strong British or Irish tilt, though Living DNA says it is working to improve ethnicity estimates in Germany and elsewhere.

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