'At 5% Neanderthal, You Are an Outlier'

By James Fallows

That is the kind of mail I am now receiving from scientists, after the revelation two days ago that I have an unusually large share of Neanderthal DNA (5%) in my genetic makeup. Plus, the accompanying revelation that my mitochondrial DNA, showing the lineage on my mother's side, resembled no other samples yet collected in a large-scale study.

Some people might find this upsetting.

Not me. I am going with it.

On avoiding over-reaction, this message from an academic in Australia:

_58752549_c0103518-neanderthal_with_shell_ornament,_artwork-spl.jpgArchaeologist here! The identification of Neanderthal DNA within the H sapiens genome is still not settled science. In fact, a recent PNAS paper (good, high profile journal. established authors) argued pretty convincingly that the results of the 2010 study everyone is still talking about are questionable.

Be proud of your heritage, but be careful of bragging about the cave man ancestors - they may just be the product of contamination.

Interestingly, the real impact of the 2010 paper to my mind is that over the last 2 years, illustrations of Neanderthals in popular venues (newspapers, TV) have gotten more and more modern-human-like (which is how archaeologists really do think they looked) and less and less cave-man-knuckledragger- like. The illustrations [e.g. at right] in these two popular articles on the PNAS paper are a great example.

And, from an academic in the U.S.:

You do have an abnormally high percentage Neanderthal component, and I wonder if that's connected to the unusual genetics of your mother. ...

I see contact with Neanderthals as having been ephemeral and primarily a result of rape by Neanderthal males of AMH [anatomically modern human] women and that the locus of that interaction happened half way up the Red Sea coast on the eastern shore. ... Your mother's DNA may be showing the most ancient European line still extant, isolated as it was in Scotland....

At 5% Neanderthal, you are an outlier, and perhaps it's time to reconsider Beowulf's Grendel and the implications of that story on our genetics. It makes no sense for a cold adapted animal, like Neanderthals, to be naked. I think they were heavily furred, and the stories of yetis, sasquatch, snowmen, and Grendel (and Gilgamesh's Humbaba also), are ancient memories, passed on in the oral tradition, of a time when we shared the earth with furry hominids.

My thought has been that we only interbred with Neanderthals (or more accurately, Neanderthal-AMH hybrids) only once, soon after the exodus from Africa, when the aboriginal population was very small so that Neanderthal genes could be spread among all descendants. There was an AMH population living with Neanderthals in the Levant as early as 90,000 years ago, who are not ancestral to us, but who could have spread Neanderthal genes to us.

However, your mother's strange genetics could indicate another insertion of Neanderthal genes at a much later date, ergo your high percentage. This would have happened long before any Celtic or Norse peoples came to the British Isles.

I dunno. I will say that my wife is looking at me a little strangely.

This article available online at:

http://www.theatlantic.com/technology/archive/2012/10/at-5-neanderthal-you-are-an-outlier/263475/