Help! I’m Baffled by My Neanderthal DNA Test Results
View taken July 8, 2010, of a mannequin of Tautavel Man presented at the prehistoric museum in Tautavel in FranceERIC CABANIS/GETTY IMAGES
October 23, 2015
Tracing Your Roots: Why can DNA tests identify ancient Neanderthal ancestry, but can only pinpoint human-ancestry admixture back several generations?
Dear Professor Gates:
I read your column “Do Most Whites Have Traces of African DNA, as I Do?” with interest. The questioner in that column was wondering whether the traces of African ancestry in her DNA test entered her family tree recently (perhaps during slavery) or in ancient times (remnants from all of humankind’s origins in Africa).
You told her, “Although some DNA tests probe into deeper ancestry, back thousands of years, the autosomal test that you took from 23andMe generally shows more recent ancestry, quite reliably over the last 100 to 200 years—in your case, since the time of slavery, when this ‘admixing’ most likely occurred. Given this information, the African DNA identified in your test is not from ancient ancestors (after all, 50,000 or so years ago, all of our ancestors were Africans, but that ancient DNA has largely disappeared) but, rather, from more recent ancestors … ”