Neanderthals and Genes.

13 May 2010

Science Daily May 6th (see www.sciencedaily.com/releases/2010/05/100506141559.htm ) the fossil record indicates modern humans differ physically from Neanderthals. In addition, the Out of Africa theory has a 'pure' unadulterated race of Homo sapiens evolve in isolation in Africa and then migrate out of that continent to colonise the rest of the world - and hominids such as Neanderthals and Homo erectus conveniently died out. This theory gained traction for a variety of reasons - it was politically expedient that all modern human races had a common ancestor (and somewhere along the line they obviously do). It repudiated 19th century (and most of the 20th century) racist stereo-typing - and it gave momentum to the idea of multi-culturism. Obviously, the Out of Africa theory is heavily politicised - but that does not mean it is not a reality. So is it true?

In this article  the emphasis is not on differences between Neanderthals and Homo sapiens, as in most studies, but their similarities. It seems we hardly differ from them - in spite of all the denials to the contrary. New research published by Science May 6th indicates we are incredibly similar to the Neanderthals at the level of proteoms - the full set of proteoms that our genes encode. In the same isssue of Science there is an article by Svante Paabo, a pioneer in palaeogenetics, and concerns the publication of the first complete genome sequence for the Neanderthals (at the Max Planck Institute in Leipzig). The genome (like that of modern humans) contains about 3 million base-pairs of nucleotides but the research concentrated on the 14,000 protein-coding segments that differ between humans and chimpanzees. The research found only 88 changes in Neanderthal protein sequences compared to those of modern human sampling - which is said to be astonishing. The functional role of those 88 proteins is yet to be established but it is expected they will prove to be neutral - and the number of differences is therefore expected to drop. They will drop even further if a bigger sample of modern humans is compared. It is thought the actual number of differences may even end up as nil - which really is astonishing.