Accuracy of DNA ancestry site questionable

Alisa Aistrup, Feature Editor

According to Genome Network, the leading source of news about genomics research worldwide, any two human beings share about 99 percent of the same genetic makeup — it is only the remaining percent that makes each person unique. In spite of those odds, consumers are driven to determine why exactly Uncle Fred is the only one in the family with blue eyes or why cousin Sally has a genetic risk for cancer.
DNA kits such as 23andMe and AncestryDNA have been around for a long time — AncestryDNA was founded in 1997 — but have become increasingly popular over the past couple of years. While both companies extract customer’s DNA to determine their genetic makeup, the two provide different information. While 23andMe provides reports on a person’s genetic risk of Alzheimer’s, Parkinson’s and other certain diseases, Ancestry concentrates less on health information and more on tracing the migration patterns of ancestors and the connections in one’s family tree.
Costs also vary between the two products. 23andMe offers two tests: a $199 version which comes with health and ancestry components and a $99 version with only an ancestry test. Ancestry only offers a $99 test that determines information about family ancestry and how that lineage connects the customer to potential ancestors.
Despite the fact that my family has always told me I was half Danish and half Mexican, my results came back to show that I am actually 40 percent German, which debunks all that my father and grandparents have told me about our great lineage from Denmark. Although we only had one relative from England who married into the family tree, my sister’s results showed that she is 60 percent English.
According to Jake Byrnes, Ancestry’s senior manager of population genomics, the explanation behind otherwise broad, questionable results is the work-in-progress procedure of comparing the genes of genetically similar individuals to that of the consumer.
“Your DNA doesn’t change, but our estimation procedures are kind of a learning experience,” Byrnes said in an 9 interview in the “Chicago Tribune.” “While we think you’re, say, 20 percent Irish, it could be as low as 5 [percent], and it could be as high as 35 [percent].”
In 2018, CBC’s “Marketplace” host Charlsie Agro and her twin sister, Carly, bought five kits — AncestryDNA, MyHeritage, 23andMe, FamilyTreeDNA and Living DNA — and mailed samples of their DNA to each company for analysis. The results were nothing less than shocking; although most of the companies sent back the same information for both women, 23andMe’s results showed that Charlsie had nearly 10 percent less “broadly European” ancestry than Carly. Charlie also had 2.6 percent French and German ancestry that her sister didn’t share.
According to a CBC article by Charlsie Agro, when 23andMe was asked why the twins didn’t receive the same results, 23andMe told “Marketplace” in an email that “even minor variations can lead its algorithm to assign slightly different ancestry estimates.”
My results seemed very accurate, and I really didn’t learn anything that I didn’t already know,” English Teacher Laura La Rue said. “You have to question the validity, though, because they make you spit in a vile to get their results. The room for human error is huge.”
Some students who have taken DNA kits don’t question the accuracy of the their results, however. Sophomore Steven Gyman took a DNA kit in 2018 and was not surprised when he received his results.
“I didn’t learn anything new,” Gyman said. “I’m Ukrainian, Russian and English, which was stuff I already knew before, but it was interesting to see the actual amount of each I was.”
Although 23andMe said that it works to report the most accurate data through the continuous development of its algorithm, 23andMe admits in an article on “MIT Technology Review” that most results are statistical estimates. However, as 23andMe increases the size of its DNA database and gathers more population data, the chance of attaining the more precise results also increases.
“The results will be more and more refined to country-specific levels versus broader assignments,” 23andMe spokesman Andy Kill said in an interview with “The Chicago Tribune.” “In cases where we can’t be country-specific but are confident in the region, we’ll make a broader region-level assignment.”
It is impossible to get an exact representation of one’s genetic makeup. As time goes on, companies like Ancestry and 23andMe will without a doubt continue to produce DNA kits, and their estimates will only get more precise.