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Ever wonder where you came from? Now with the help of National Geographic’s Genographic Project, you can find out. Population geneticist Dr. Spencer Wells and a team at National Geo will send you a Geno 2.0 test kit that collects DNA samples from your cheeks. After sending them back and waiting a few weeks, you can get online results showing from where your maternal and paternal ancestors migrated.
I did this recently and discovered several interesting facts. The test compares a person’s genetic makeup on thousands of DNA identifiers. The team has evaluated over 660,000 individuals from 140 different countries according to the website and the booklet “Geno 2.0: Your Story. Our Story. The Human Story.” Participants must be 18 years or older, or have the explicit consent of their parents or guardians.
Do You Have Neanderthal DNA?
First, the bad news: I found that 2.3 percent of my genetic code is from the Neanderthals and 2.6 percent from the newly-discovered Denisovans species which separated from humans around 500,000 years ago. Initially, this worried me knowing the former species’ reputation for brutish and anti-social behavior (although some scientists now have proposed a revisionist model suggesting Neanderthals were more social than commonly thought). But the National Geographic team reassured me this is not unusual. Indeed, most non-Africans are about 2 percent Neanderthal in their gene pool. Of course, I still had to deal with the fact that I was slightly above average on this dimension, but it at least provides some explanation for my nerdish mannerisms. I no longer have to explain mood shifts or irascible behavior to my wife. I merely tell her these features are part of my genetic makeup and not things that are easily controlled.
On the more positive side, the genetic test revealed informative details about my geographic origins. According to the scientific analysis, my makeup is 42 percent Northern European, 37 percent Mediterranean, and 19 percent Southwest Asian (with 2 percent unaccounted for). Roughly 8,000 years, my distant ancestors likely were part of the Neolithic population expansion from the Middle East moving north and west towards Europe from the Fertile Crescent. The Asian component arises from the fact that nearly all Europeans have mixed with those from Southwest Asia over the past tens of thousands of years.
A View in the Lives of Past Ancestors
This genetic test allows you to do a deep dive into your ancient ancestors going back 75,000 years, subject of course to the vagaries of genetic testing and scientific inquiry. According to the National Geographic team, nearly all people alive today date back to male African ancestors who lived there 140,000 years ago and female East Africans born 180,000 years ago. There apparently were other people living around that time but this African group dubbed “Y-chromosome Adam” and “mitochondrial Eve” are the only people whose chromosome lineage has survived through the current period.
About 75,000 years ago, the BT branch of this chromosome tree arose containing the M42 genetic marker. These people’s descendants would move out of Africa to the Middle East and India. Those with the M168 branch were the first to leave the African Rift Valley in contemporary Kenya, Ethiopia, or Tanzania around 70,000 years ago, possibly as a result of climate change. The melting of northern hemisphere ice sheets brought water to formerly arid lands which encouraged animal and human migration into the Arabian peninsula and Southeastern Asia.
My Parents’ Lineage
On my mother’s side, my lineage dates back 67,000 years ago to the L3 genetic branch of East Africa. There were two groups that populated the rest of the world, the M and N haplogroups. My branch is on the N side and likely moved through the Nile basin into the eastern Mediterranean area, possibly Turkey. For a time, they co-existed with the Neanderthals, before the latter died out (but not before sharing certain recreational interests that apparently led to my small bit of Neanderthal code). Thanks great-great-great-great Grandpa for that fling, which has reverberated genetically through the ages!
My paternal ancestors likely were living in the Middle East, Iran, or parts of Central Asia with the M89 branch. The grass-covered plains attracted wild game and my forbearers were smart enough to follow the food trail. During the Paleolithic Era 35,000 years ago, my predecessors were part of the M45 branch living in Central or Southern Asia. Over the next several thousands of years, these individuals settled Europe, the Middle East, and South Asia.
By 25,000 years ago, my maternal predecessors had gone through the R and then T branches as hunter-gatherers or subsistence fisherman. And by 10,000 years ago, many of this group had settled in the Fertile Crescent and domesticated plants and nuts. They were the Neolithics and became the world’s first true agriculturalists.
This shift from hunter-gathering to farming allowed larger populations to form and early civilizations in Turkey, Syria, Iraq, and elsewhere in the Middle East to flourish. I would like to think that my family played some important role in ancient Mesopotamia, but it is more likely we were of peasant stock since that was true for nearly everyone at that time.
After learning about my genetic ancestry, I felt mildly cosmopolitan. I hadn’t considered that my ancestors had started out in Africa, traveled through the Middle East and Central Asia, and ended up at some much later point in Northern Europe. This journey took place over 75,000 years and likely contained many twists and turns along the way. Too bad, these people did not write and keep travel journals. The next time I visit Turkey, India, or Great Britain, I am sure to experience a sense of déjà vu.
This undertaking also made me appreciate the insights offered by genetic testing. As test kits come down in price and become a consumer item, scientists likely will discover interesting things about diseases, genetics, and medicine. This knowledge will inform health care and allow us to target medications more precisely than is true today.
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Commentary
Trace Your Genetic Ancestry Through National Geographic’s Genographic Project
April 17, 2014