Oldest Human Genome Reveals When Our Ancestors Mixed With Neanderthals

sciencehabit writes DNA recovered from a femur bone in Siberia belongs to a man who lived 45,000 years ago, according to a new study. His DNA was so well preserved that scientists were able to sequence his entire genome, making his the oldest complete modern human genome on record. Like present-day Europeans and Asians, the man has about 2% Neanderthal DNA. But his Neanderthal genes are clumped together in long strings, as opposed to chopped up into fragments, indicating that he lived not long after the two groups swapped genetic material. The man likely lived 7000 to 13,000 years after modern humans and Neanderthals mated, dating the mixing to 52,000 to 58,000 years ago, the researchers conclude. That's a much smaller window than the previous best estimate of 37,000 to 86,000 years ago.

Comments

Re:Bone a Neanderthal

[Teresita]

Someday they'll figure out "Neanderthal" is a completely artificial distinction, like "White Aryan", and the scientific consensus will be that Neanderthals R Us.

Question for sequencing expert.

[tloh]

How accurate is it for the media to say a "complete" genome was sequenced? I know a little molecular biology and have been lead to believe that certain types of DNA, (centromeres, telomeres, other such regions with lots of repetitive sequences or "fragile sites") are very hard to sequence reliably. Are these "swept under the rug" in a "complete" sequence? Perhaps a related question, how are non-coding regulatory portions of chromosomes handled in whole genome analysis?

and what do we learn

[Anonymous Coward]

being interoperable with posix doesn't stop openbsd from becoming extinct, but in every of today's UNIXes (except older unixes of course) there is a tiny part of openbsd, but that isn't harmful.

its nice to combine human genetics and netcraft.

Re: Exinction

[Half-pint HAL]

The Cro-Magnon sub-species disappeared, too, and modern human Caucasian and Asian sub-species are the results of that mixing.

Modern thinking suggests there was no Cro-Magnon subspecies, and that scientists of the time were actively looking for differences, hence ignored that the dimensions of the cro-magnon specimens were within the variation found within modern humans. Remember, prior to World War II, "racism" was more or less considered a branch of science. In Frank Herbert's Dune, there is an obsession with finding "humans" and separating them from "animals" by breeding, and while it's easy to rationalise that away as a Nazi reference, but that's just choosing to ignore that a lot of people felt that way elsewhere. While most of the world abandoned eugenics after the war, there are some who lament the Nazis giving a "bad name" to it. Eugenics even continued in parts of the US, through mandatory sterilisation of the mentally disabled, which was extended to African Americans with poor school records. There was a continuing assumption among many that black Africans were an "inferior race" and therefore just pollution to the genestock. Elsewhere, the colonial powers justified their continued occupation of their remaining territories through the condescension that these foreign types just weren't capable of ruling their own countries, and so we were doing them a favour by lending them our superiority. For all this time, scientists were looking for individual homonid species/subspecies as ancestors of the "races" that we had invented in modern populations based on little more than melatonin levels and eye shape.

Yes, I've gone off at a tangent. A very long tangent. My point is that in matters of human evolution, generations of science were led by the nose in order to rationalise the prejudices of the privileged few. Modern science, thankfully, has proper data to work with -- DNA. Neanderthal DNA has been sequenced from Neanderthal fossils, and it differs from Modern Human DNA in ways that are measurable and quantifiable. It denies the old claim that white man was neanderthal and therefore a distinct race from Africans, or that Basques are Cro-Magnon and a different species from everyone else in Europe.

Neanderthaler was different enough to be of note and is extinct. A few genetic markers remain, but most of the unique DNA is lost.

But humans aren't like this. Even if we do generally prefer mates in our own subspecies, most of us do find many members of other subspecies physically attractive, and we'll mate with them given the opportunity. This means that we really are all the same species. We now have good evidence that the Neandertals were merely another subspecies, because when they had the opportunity, they did interbreed with those slender, dark-skinned folks who migrated into their territory. They did so often enough to produce a new subspecies that's physically distinct from either of the earlier two (or three or more).

I find your use of human subspecies troubling -- it harks back to the institutional racism of pre-genomic science (there was a point to my earlier rambling after all). Neanderthal may have been a subspecies rather than a fully-fledged species (debating that would be irrelevant here) and that definition would be based on marked genetic differences and rare interbreeding with early modern human populations. But the genetic differences between human racial groups is not on the same level as subspecies -- in fact, as I understand it, it's less than between different breeds of domestic dog, and all domestic dogs are lumped under one single subspecies: canis lupus familiaris.

Even though you didn't intend to, your argument implies that the difference between Neanderthaler and Modern Human is on the same order of magnitude as the difference between black African and white European. That's not a road we want to start back down.