While he can't say for certain what accounts for the difference, Gerstein suspects it has to do with the algorithms each company uses to crunch the DNA data.
Marketplace sent the results from all five companies to Gerstein's team for analysis.
Mark Gerstein, a computational biologist at Yale University. "The fact that they present different results for you and your sister, I find very mystifying," said Dr. And while Carly's Eastern European ancestry was linked to Poland, the country was listed as "not detected" in Charlsie's results. The identical twins also apparently have different degrees of Eastern European heritage - 28 per cent for Charlsie compared to 24.7 per cent for Carly. She also has French and German ancestry (2.6 per cent) that her sister doesn't share. According to 23andMe's findings, Charlsie has nearly 10 per cent less "broadly European" ancestry than Carly.