Hat-tip April Cunningham!

It’s important to understand what these tests actually mean, as well as their limitations. First up: the term “ethnicity.” It generally connotes shared nationality, language, and culture, but even people who study race and ethnicity acknowledge disagreement about the precise definition of the term. Suffice to say, geneticists concur that it’s a social construct. Altogether, 94 percent of genetic variation occurs within so-called racial groups, meaning there’s much more biological difference within races than between them. This holds even when researchers study regional ethnic groups; they find a lot more genetic diversity inside each group than between different groups.

Read more:

Harrington, C. (2020, October 2). Your ‘ethnicity estimate’ doesn’t mean what you think it does. Wired. https://www.wired.com/story/your-ethnicity-estimate-doesnt-mean-what-you-think-it-does/