Neanderthal Genes ‘Survive in Us’

Paul Rincon, BBC, May 6, 2010

Many people alive today possess some Neanderthal ancestry, according to a landmark scientific study.

The finding has surprised many experts, as previous genetic evidence suggested the Neanderthals made little or no contribution to our inheritance.

The result comes from analysis of the Neanderthal genome–the “instruction manual” describing how these ancient humans were put together.

Between 1% and 4% of the Eurasian human genome seems to come from Neanderthals.

But the study confirms living humans overwhelmingly trace their ancestry to a small population of Africans who later spread out across the world.

The most widely-accepted theory of modern human origins–known as Out of Africa–holds that the ancestors of living humans (Homo sapiens) originated in Africa some 200,000 years ago.

A relatively small group of people then left the continent to populate the rest of the world between 50,000 and 60,000 years ago.

While the Neanderthal genetic contribution–found in people from Europe, Asia and Oceania–appears to be small, this figure is higher than previous genetic analyses have suggested.

“They are not totally extinct. In some of us they live on, a little bit,” said Professor Svante Paabo, from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

Professor Chris Stringer, research leader in human origins at London’s Natural History Museum, is one of the architects of the Out of Africa theory. He told BBC News: “In some ways [the study] confirms what we already knew, in that the Neanderthals look like a separate line.

“But, of course, the really surprising thing for many of us is the implication that there has been some interbreeding between Neanderthals and modern humans in the past.”

John Hawks, assistant professor of anthropology at the University of Wisconsin-Madison in the US, told BBC News: “They’re us. We’re them.

“It seemed like it was likely to be possible, but I am surprised by the amount. I really was not expecting it to be as high as 4%,” he said of the genetic contribution from Neanderthals.

The sequencing of the Neanderthal genome is a landmark scientific achievement, the product of a four-year-long effort led from Germany’s Max Planck Institute but involving many other universities around the world.

The project makes use of efficient “high-throughput” technology which allows many genetic sequences to be processed at the same time.

The draft Neanderthal sequence contains DNA extracted from the bones of three different Neanderthals found at Vindija Cave in Croatia.

Retrieving good quality genetic material from remains tens of thousands of years old presented many hurdles which had to be overcome.

The samples almost always contained only a small amount of Neanderthal DNA amid vast quantities of DNA from bacteria and fungi that colonised the remains after death.

The Neanderthal DNA itself had broken down into very short segments and had changed chemically. Luckily, the chemical changes were of a predictable nature, allowing the researchers to write software that corrected for them.

Writing in Science journal, the researchers describe how they compared this draft sequence with the genomes of modern people from around the globe.

“The comparison of these two genetic sequences enables us to find out where our genome differs from that of our closest relative,” said Professor Paabo.

The results show that the genomes of non-Africans (from Europe, China and New Guinea) are closer to the Neanderthal sequence than are those from Africa.

The most likely explanation, say the researchers, is that there was limited mating, or “gene flow”, between Neanderthals and the ancestors of present-day Eurasians.

This must have taken place just as people were leaving Africa, while they were still part of one pioneering population. This mixing could have taken place either in North Africa, the Levant or the Arabian Peninsula, say the researchers.

Professor Stringer added: “Any functional significance of these shared genes remains to be determined, but that will certainly be a focus for the next stages of this fascinating research.”

The Out of Africa theory contends that modern humans replaced local “archaic” populations like the Neanderthals.

But there are several variations on this idea. The most conservative model proposes that this replacement took place with no interbreeding between modern humans and Neanderthals.

Unique features

Another version allows for a degree of assimilation, or absorption, of other human types into the Homo sapiens gene pool.

The latest research strongly supports the Out of Africa theory, but it falsifies the most conservative version of events.

The team identified more than 70 gene changes that were unique to modern humans. These genes are implicated in physiology, the development of the brain, skin and bone.

The researchers also looked for signs of “selective sweeps”–strong natural selection acting to boost traits in modern humans. They found 212 regions where positive selection may have been taking place.

The scientists are interested in discovering genes that distinguish modern humans from Neanderthals because they may have given our evolutionary line certain advantages over the course of evolution.

The most obvious differences were in physique: the muscular, stocky frames of Neanderthals contrast sharply with those of our ancestors. But it is likely there were also more subtle differences, in behaviour, for example.

Dr Hawks commented that the amount of Neanderthal DNA in our genomes seemed high: “What it means is that any traits [Neanderthals] had that might have been useful in later populations should still be here.

“So when we see that their anatomies are gone, this isn’t just chance. Those things that made the Neanderthals apparent to us as a population–those things didn’t work. They’re gone because they didn’t work in the context of our population.”

Researchers had previously thought Europe was the region where Neanderthals and modern humans were most likely to have exchanged genes. The two human types overlapped here for some 10,000 years.

The authors of the paper in Science do not rule out some interbreeding in Europe, but say it was not possible to detect this with present scientific methods.

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  • Robert Binion

    To assert that blacks are lean and swift is racism, that Neanderthal are stocky and strong science. BBC seem unable to sip their Darwin straight.

  • highduke

    Read ‘Total Man’ by the under-rated obscure Cornish psychiatrist Stan Gooch who used sociology, linguistics, folklore, history and anthropology to show as early as 1971 that Eurasians’ assimilation of Neandertal made us different from Africans.

  • Alexandra

    No such thing as Neanderthals. Evolution is just a theory.

  • LaTwatta Lincoln

    I find it very interesting that it’s perfectly acceptable for scientists to discuss THIS type of human breeding — but it is still totally UNACCEPTABLE for scientists to write about scientific material on human breeding such as one finds in The Bell Curve, or in some of the books one can find on this site. As long as the research doesn’t tell the truth about Africans, then I guess it’s OK.

  • Anonymous

    Research suggests Euro Asians are a hybrid of homo-sapiens and homo-Neanderthals. That hybrid expanded from the Gaza strip area, the southern extent of homo-Neanderthals, to conqueror the world and reach for the stars. In the process the hybrid drove homo-Neanderthals to extinction and left homo-sapiens in Sub-Saharan Africa to stagnate rather than evolve.

  • Dan

    I was on the understanding that Euroasians evolved from Neandethals. In 2008, wasn’t there the discovery of some 1.8 million yr old Homo-Erectus’ and didn’t reconstruction of Neandethals show that they clearly looked European which all seems to show that we didn’t come from Africa 60’000 yrs ago??

  • John Engelman

    4 — Dan wrote at 5:49 AM on August 31:

    I was on the understanding that Euroasians evolved from Neandethals. In 2008, wasn’t there the discovery of some 1.8 million yr old Homo-Erectus’ and didn’t reconstruction of Neandethals show that they clearly looked European which all seems to show that we didn’t come from Africa 60’000 yrs ago??

    ——-

    Caucasian and Oriental DNA is far more similar to black DNA than it is to Neanderthal DNA.

    According to the Out of Africa theory of human evolution, human evolution began about six million years ago when the development of the Rift Valley divided the common ancestor of humans and Chimpanzees.

    Somewhat less than a million years ago members of a primitive human species called “Homo Erectus” left Africa. These had bodies similar to those of modern humans, but their brains were much smaller. In the Near East and Europe these evolved into Neanderthals. Further east less evolution occurred.

    Because the human population was much larger in Africa, evolution was moving faster there. A large gene pool will usually evolve faster than a small gene pool, because there is more scope for beneficial mutations, and there is more intra species competition.

    Modern humans evolved in Africa from 100,000 to 200,000 years ago. About 60,000 years ago one hundred to several hundred of these modern humans left Africa. These were less powerful than the Neanderthals they encountered, but more intelligent.

    The recent finding that there was some genetic communication between the modern humans who left Africa and the Neanderthals does not change the out of Africa theory. Of genes that are uniquely human, Caucasians and Orientals only share about five percent with Neanderthals. The rest they share with blacks.

    The ancestors of Caucasians who lived 60,000 years ago would not have been served in Woolworth lunch counters in the South 60 years ago. They probably would have resembled the bushmen of southern Africa.

  • Dan

    That’s fine, if you believe the OoA Theory! Cromagnon Man was around 40’000 yrs ago and Neandathal became exstint around 25’000 yrs ago. They also had blue and green eyes. We had an Ice Age around 60’000 yrs ago and at the time Europeans were moving south so it dooesnt make sense for the Africans to move north, does it? The OoA Theory fails on many counts.

  • Dan

    Firstly, evolution is not a theory it is a FACT! secondly, the OoA has been discredited by science and new findings. The Africans were hardly more intelligent than the Neandathols they supposedly encountered. The Neandathols had musical instruments and the ability to cope with their environment as did Cromagnon Man who came on the scene and shared the Continent with them.

    DNA has shown that Europeans and people in the Near east share DNA with this ancestor and, furthermore, China has fossils going back over 100’000 yrs and is clearly modern to the chinese so OoA fails there too. And in DNA? there are medisines that are ineffective with Africans. For example, the heart drug enalapril reduces blood pressure in white patients but has little effect on blacks. MtDNA does not prove that Eve was African either. In fact Henry Gee of the journal ‘Nature’ descibed the studies on MtDNA as ‘garbage’.

    Homo Erectus certainly started in the tropics but evidence has shown that they migrated out across the planet nearly 2 million yrs ago (fossils found in Georgia, 2008)where they adapted, mutated and evolved.

  • margaret

    Here is another refutation of that old black Muslim legend of out of Africa. The original NOI theory back in the 1930’s was that an evil wizard Mr. Yacub invented us blue eyed devils.

    Then along came 2, just 2 lesbian Marxists at one of our most communist infested Universities, Cal Berkeely who revived the Mr. Yacub story and the useful idiots accepted it.

    170,000 year old Homo Erectus bones have just been discovered in France.

    Neanderthal skull fragment discovered in Nice

    Riviera Times

    Wednesday, August 24, 2011

    Part of a prehistoric skull, dating back 170,000 years, has been discovered during an archaeological dig in Nice. Experts say the discovery could reveal important clues to the evolution of humans. Students Ludovic Dolez and Sébastian Lepvraud were working on the excavation site, Lazaret Caves, on 13th August, when they came across the partial remains of a forehead belonging to a Homo Erectus.

    Paleontologist Marie-Antoinette de Lumley, who has been in charge of excavation at Lazaret since 1961, said the bone is an important find: “It belonged to a nomad hunter, less than 25 years old.

  • John Engelman

    Some American Renaissance posters seem to want to believe that Caucasians are descended from Neanderthals, rather than the modern humans who left Africa about sixty thousand years ago, and who resembled blacks.

    If millions of Neanderthals survived to the present time they would present social problems of unbelievable severity. They were much less intelligent than any of the existing races, and much more formidable physically. They would only have been able to learn the simplest tasks. With no tolerance for boredom they would have preferred violent crime.

    As dangerous as large carnivorous animals, they would have sometimes eaten their crime victims.