Neanderthal DNA Breaks Human Tie

NEW YORK -- A hauntingly brief but significant message extracted from the bones of a Neanderthal who lived at least 30,000 years ago has cast new light both on the origin of humans and Neanderthals and on the long-disputed relationship between the two.

The message consists of a short strip of the genetic material DNA that has been retrieved and deciphered despite the age of the specimen. It indicates that Neanderthals did not interbreed with the modern humans who began to supplant them from their ancient homes about 50,000 years ago.

The message also suggests, said the biologists who analyzed it, that the Neanderthal lineage is four times older than the human lineage, meaning that Neanderthals split off much earlier from the hominid line than did humans.

The finding, made by a team of scientists led by Dr. Svante Paabo of the University of Munich in Germany, marks the first time that decodable DNA has been extracted from Neanderthal remains and is the oldest hominid DNA so far retrieved. It was extracted from the original specimen of Neanderthals, found in the Neander valley near Dusseldorf, Germany in 1856 and now in the Rheinisches Landesmuseum in Bonn.

"This is obviously a fantastic achievement,'' said Dr. Chris Stringer, an expert on Neanderthals at the Museum of Natural History in London.

Many anthropologists had tried to extract DNA from Neanderthal bones without success. "Clearly, it's a coup,'' Dr. Maryellen Ruvolo, an anthropologist at Harvard University, said of the Munich team.

The Neanderthals were large, thick-boned individuals with heavy brows and a brain case as large as that of modern humans but stacked behind the face instead of on top of it. They lived in Europe and western Asia from 300,000 years ago until they died out about 270,000 years later.

For the latter part of that period they clearly coexisted with modern humans but the relationship between the two groups, whether fraternal or genocidal, has been debated ever since the first Neanderthal was discovered. Early humans and Neanderthals may have interbred, as some scientists contend, with modern Europeans being descended from both. Or the two hominid lines may have remained distinct, with humans displacing and probably slaughtering their rivals.

The new finding, reported in Friday's issue of the journal Cell, comes down firmly on the side of Neanderthals having been a distinct species that contributed nothing to the modern human gene pool.

Dr. Ian Tattersall, a paleontologist at the American Museum of Natural History, said the finding "fits well into my view of the fossil record,'' although there was still a "very tenacious notion of Neanderthals having given rise to Homo sapiens or interbred with them.''

The new work is also being praised by scientists who study ancient DNA, a lively new field that has included reports of DNA millions of years old being retrieved from dinosaur bones, fossil magnolia leaves and amber-entombed insects. Although these reports have appeared in leading scientific journals, other scientists have been unable to reproduce them. In at least in one case the supposed fossil DNA was contaminated by contemporary human DNA.

But a leading critic of these claims of ancient DNA extraction, Tomas Lindahl of the Imperial Cancer Research Fund in England, has called it "arguably the greatest achievement so far in the field of ancient DNA research.''