DNA Molecule

A schematic of a DNA molecule. (Public Domain image from Wikimedia commons.)

I started with the family tree my mother wrote out in my baby book, added research from relatives on both sides of my family, and generally have a pretty good idea of where my ancestors came from. I’ve traced all branches back to before the Civil War, and in some cases to before the Revolutionary War. My baby book lists English, Irish, Scotch, Dutch and French origins, though quite a few generations back. I allegedly have some French-Canadian trapper ancestry though my maternal grandmother, and on that basis and physical appearance we sometimes think the family has a little Native American background. So I was interested in what Genographics would make of me.

Genographics give the percent of your total ancestry matching native groups from 9 different regions. The regios are:
Northeast Asia
Mediterranean
South African
Southwest Asian
Native American
Oceania
Southeast Asia
Northern European
Sub-Saharan Africa

Well, mine showed no Native American. My DNA results for the whole genome are fairly typical European: 45% Northern European, 37% Mediterranean and 16% Southwest Asian. That doesn’t rule out the possibility of a very tiny contribution from Native Americans, but it certainly doesn’t confirm it.

This doesn’t mean my recent ancestors came from these parts of the world! My profile is very similar to that of people who’ve lived for several generations in England, and even closer to those from Germany. The mixing probably took place several thousand years ago.

The Northern European component probably represents the original hunter-gatherer population of Northern Europe. These people may be descended from the Cro-Magnons. Genographics doesn’t say anything about skin or eye color, but I suspect blue eyes and light hair evolved in this component simply because they lived for a long time in a relatively low-sunlight environment where these traits would have had little cost and considerable benefit in production of vitamin D.

The Mediterranean component probably represents the partial replacement (with considerable interbreeding) of the hunter-gatherers by Neolithic farmers moving north and west from the early farming communities of the middle east. This movement is thought to have started around eight thousand years ago.

The Southwest Asian component probably had a similar origin, perhaps coming from father east in the fertile crescent, the origin of western Eurasian agriculture.

So no surprises, just a rather bland typical European background. What I found most interesting was the Neanderthal and Denisovian fractions of my genome – but more of that later.

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