I Can’t Believe My Ethnic DNA Test Results!

Tracing Your Roots: His black grandma’s claim that her dad was from Mumbai is confirmed by testing. But how?

 
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“I was just reading your column, ‘I'm Creole. Why Do I Have South Asian DNA?’ I, too, have ancestral roots in Andhra Pradesh region of India and South Africa. I identify—and the rest of the world identifies me—as a black male. However, a test I took from DNA Tribes says I also have large concentrations of DNA from people who now live in East Timor, which is above Australia. I'm confused.

"You see, I wanted a job with U.S. government and could not get one. I decided to prove ‘Indian’ ancestry that my grandmother told me about so I could get into a tribe, maybe via the Dawes rolls, and eventually get identified as Native American. I figured that could help me get a Bureau of Land Management job with the Dept. of Interior. 

"Anyway, I swabbed cheek, sent in test to DNA Tribes and the results were ‘South African’ and ‘East Indian.’ I said to my 89-year-old ‘black’ grandmother from Shreveport, La., ‘I thought you said we had “Indian” in our family,’ to which she replied, ‘We do. My father is from Bombay!’ I told her that I had heard her say that before but dismissed it because she was almost 90 and could not have possibly meant we had East Indian in us. Anyway, I don't get the Indian/South African connection. Was there some sort of trade with Louisiana? And how did East Timor get into the picture?” —D. Brown

Today, more than ever, there is a wide variety of DNA testing companies from which people can choose. Each of these companies can offer different types of tests, use their own methodologies and provide their own unique analysis of the results. As such, a good understanding of the type of test you had and what the accompanying analysis means can help explain some unexpected results.

Understanding the Results of Your Test

The results you received are from an autosomal DNA test. Such a test will analyze genes inherited from both your mother and father, giving you a range of information about your ancestry throughout time. It differs from y-DNA and mtDNA (mitochondrial) tests, which just give you information about your direct paternal or maternal ancestors, respectively.

CeCe Moore, a genetic genealogist we consulted, notes, “Your DNA report is based on the two values (paternal and maternal) found at 15 genetic markers. This is relatively few [markers] when compared to those found across the entire genome, so it may not be representative of your overall ancestral origins or ‘admixture,’ but instead reflect portions of it.”  

Moore further explains that the test that you took compared your 15 genetic markers to those of reference populations from around the world. “In your case, they have accurately detected that you have ancestry from India and Africa, so that is a good start, but perhaps not the complete picture,” she notes, given that relatively few markers were used. 

She continues, “The DNA you inherited from your Indian great-grandfather would make up only about one-eighth of your admixture (12.5 percent), so your African ancestry is likely more dominant in reality, which is not reflected in these results. This type of DNA test that analyzes genetic markers as a package, rather than individually or in short runs, works best for those with ancestry concentrated in one region. Since African Americans often have ancestors from diverse populations, predicting their ancestral origins using this method can be a challenge.” Given the limitations of a 15-marker autosomal DNA test, it may not be the best option for African Americans seeking to find their ancestral origins.

There’s one more thing to keep in mind, according to Moore: “The list of your top population matches doesn't necessarily mean that you have ancestry from each of those regions, but rather that your genetic signature, as defined by these 15 markers, resembles that of people living in those regions more closely than [that of people] in other places in the world. Although your genetic signature is found with the most frequency in the Kapu Reddy people of India, it is also seen in the Tswana people of South Africa, as well as the people of East Timor.”

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