When you get your DNA tested by a commercial testing service, you receive a percentage of “what you are”. My percentage is something like 37% Chinese, 26% British, etc. But is that true? Am I really exactly that amount of Brit?
First, you have to understand how the whole thing works. The DNA testing companies (Ancestry, 23andMe, etc.) take your DNA and they compare it to the people in their database. The people that are representative of a certain region are from families in which they all lived in that region for at least three generations. That’s not the easiest thing to find so no company has been able to completely map the globe with DNA. That’s why we get regions instead of specific places and why some regions seem really really really big (like why Ireland gets sucked into “British Isles” sometimes).
The companies tell you what their ancestral populations are so you can check before you choose a place to test. (You can find Ancestry’s here, 23andMe here, Family Tree DNA here, Living DNA here, and MyHeritage here.) In order to be competitive, some have specialized in particular locations so you really might want to take a look. Since I’m Eastern European, I went with 23andMe first to see if I could narrow down the exact region I’m from.
All of this being said, DNA testing has gotten pretty popular and as more people are added to each database, the companies are fine tuning their results to make them even more accurate. I did my first DNA test in 2013 and I still get new information emailed to me from 23andMe because their available results are still changing. Overall, the short answer is: yes, it’s pretty accurate. It won’t give you the exact towns your ancestors lived in but if it tells you that you’re 55% Swedish, you’re Swedish. They have no reason to just make that up and assign new ethnic backgrounds to people.
Just kidding. You might be but let’s call it a slimmer-than-it-used-to-be chance. I also thought that I was Native American by a pretty significant amount based on a tall tale my great-grandmother told everyone. As an adopted person, she made up a backstory for herself that involved a Native American woman getting pregnant by an Irish traveling minister and everyone in my family took it for granted that we were part Native American/Irish. However, DNA testing reveals that my great-grandmother was Irish and Swedish and British. She was not, however, even a bit Native American.
All of the testing services have the ability to show Native American ethnicity, so if you have none at all that’s a little suspicious re: you being Native American but it’s not a complete “no”. Interestingly, Native American ethnicity might show up as Asian in some testing services because of how people originally migrated so if you have some Asian in your report that doesn’t make any sense, that could be where your Native American ethnicity is showing up.
The reality is that the “part Native American” myth is really common in American families and much more common than actual Native American ancestry appears to be. In fact, some Native American heritage stories started because there was actually an Asian or African ancestor and the Native American idea was more socially acceptable for whatever reason.