FROM A NEANDERTHAL BONE
January 21, 2001
About 10 kilometers east of Dusseldorf in Germany, in the valley of the Dussel, there is a little town called Neander. One hundred and forty-one years ago, in the summer of 1856, some workmen broke into a cave to get at the limestone inside and discovered a set of ancient bones.
Most of the bones were smashed to bits by the workmen, but some of the bones, including part of the skull, survived, and the skeleton was soon recognized by anthropologists as belonging to an ancient race of men who came to be known as the Neanderthals.
A Neanderthal fossil had actually been discovered some years earlier in Gibraltar, but not recognized as such. Neanderthal-like fossils have also been found in France, Spain, Italy, Yugoslavia, Iraq, China, Java, and Israel.
For more than a century, one of the central questions in paleoanthropology has been whether modern man evolved from this race -- or was the Neanderthal a separate branch that became extinct? Until recently, the primary laboratory method of investigation of such a question was analysis of the morphology of bone fragments.
This week, the field of paleoanthropology has apparently crossed an important watershed, as M. Krings et al (University of Munich, DE; Pennsylvania State University, US) report the first analysis of DNA from an extinct human, in this case DNA extracted from the actual Neanderthal skeleton found near Dusseldorf in 1856.
The key to the investigation was the analysis of mitochondrial rather than nuclear DNA. Mitochondrial DNA is usually present in concentrations two or three orders of magnitude greater than nuclear DNA, and they were able to find enough of it still intact to amplify with the PCR technique and piece together a total DNA sequence of 379 base pairs. Comparison of this sequence with contemporary human sequences leads to the conclusion that Neanderthal and modern man are separate evolutionary lines, and that the latter did not evolve from the former.
The work will have to be replicated with other Neanderthal fossils, but most paleoanthropologists are excited by the results and expect them to be confirmed. The technology of evolutionary paleoanthropology has evidently now progressed from caliper measurements of bones to measurements of bone DNA fragments.
(Cell 11 Jul 97) (Science-Week 18 Jul 97)
http://www.scienceweek.com/
NET HUNTERS / Y CHROM. EVIDENCE / NEANDERTHAL DNA
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