Hereâ€™s the question: Do people really make â€œlife-changingâ€ decisions based upon the results of a genetic genealogy test? This phrase is often stated but is seldom supported with actual facts or case studies. And Iâ€™ve certainly never seen an estimated percentage of people who have made these types of â€œlife-changingâ€ decisions, which would really help further the discussion.
Earlier this month, Harvard Professor Henry Louis Gates, Jr. announced the launch of his new genetic genealogy company, AfricanDNA.com. According to the press release, â€œthe precedent-setting site is the only company in the field of genetic genealogy that will provide African Americans with family tree research in addition to DNA testing.”
The company will offer two tests – the Maternal Test (testing mtDNA) and the Paternal Test (testing Y-DNA). The testing will be done at the Genomic Analysis and Technology Core laboratory at the
â€œFor $888, African DNA, which works with Houston-based Genealogy By Genetics Ltd., will include a family tree as far back as census records allow. For most African-Americans, that is usually 1870, when their last names began to be recorded in post-slavery
The idea that a personâ€™s mtDNA or Y-DNA can be traced back to a specific location or ethnic group in
â€œthe large migrations of African people over the last 3,000 years mean that a typical black American’s DNA might have an exact match with somebody living today in
Ghana— but also Cameroon, Kenya, Angola, Nigeriaand .â€ Sierra Leone
Yesterday, an article by Ron Nixon in the New York Times entitled â€œDNA Tests Find Branches But Few Rootsâ€ discussed Dr. Gatesâ€™ new company. (Sidenote: Nixon writes that â€œan estimated 460,000 people have taken genetic tests to determine their ancestry or to expand their known family trees, according to Science magazine.â€ I recently estimated that number to be higher.)
Nixonâ€™s article looks at the scientific feasibility of using the results of genetic genealogy testing to pinpoint a specific location or ethnic group as the source of a personâ€™s mtDNA or Y-DNA. I agree with the general conclusion that this is very difficult (often even impossible) and potentially misleading.
Thus, my disagreement is NOT with the discussion of the science in the article â€“ in fact, I think Nixon does a great job of looking at both sides of the issue. Instead, I disagree with the following from Nixonâ€™s article, quoting Troy Duster (Professor of Sociology at
“People are making life-changing decisions based on these tests and may not be aware of the limitations,” he added. “While I don’t think any of the companies are deliberately misleading customers, they may have a financial incentive to tell people what they want to hear.” [emphasis added].
This brings me back to my original question: Do people really make â€œlife-changingâ€ decisions based upon the results of a genetic genealogy test?
In my view, there are two basic assertions underlying the â€œlife-changingâ€ statement: (1) people are relying on the results of genetic genealogy tests to make decisions, and (2) these decisions are extremely important decisions (such that they are â€œlife-changingâ€). For instance, deciding to borrow books from the library about a specific geographic area or researching an ethnic group of people cannot be the type of decisions referred to in articles because they are not â€œlife-changing.â€
So what type of decisions are being referred to, and how often are people really making them? Have enough of the supposed 460,000 people who have been tested made such an important decision that it is â€œlife-changingâ€? As a scientist, Iâ€™m skeptical but certainly open to evidence. If you think that this is a real problem, please let me know in the comments why you think so. Or, if genetic genealogy has led you to make a â€œlife-changingâ€ decision, I would honestly like to hear about it.
Thereâ€™s more discussion of the NYT article at John Hawks Anthropology Blog, â€œWherein the New York Times says Hawks was right.â€ And Iâ€™m sure there will be a lot more coverage and conversation among genetic genealogists.