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Partial Draft of Neandertal Genome
New sequencing technologies revive ancient DNA.
The first chunk of the Neandertal genome was published today in the journal Nature. It reveals that modern humans and our ancient cousins diverged about 500,000 years ago. The sequence, derived from a 38,000-year-old bone fragment found in a cave in Croatia, was made possible by a new sequencing technology developed by 454 Life Sciences . According to Michael Egholm, one of the 454 Life Sciences project’s leaders, who talked to Technology Review in September, the Neandertal genome will shed light on the genetic changes that make us uniquely human. “We believe we can use the Neandertal genome as a signpost for our own genome,” he says. “Our approach is to look at the 35 million base pair differences between chimp and man. Then we ask a simple question: Is Neandertal like chimp or human on those sites?” (Click here for the full text of the Q&A.)
From the paper:
Neanderthals are the extinct hominid group most closely related to contemporary humans, so their genome offers a unique opportunity to identify genetic changes specific to anatomically fully modern humans. We have identified a 38,000-year-old Neanderthal fossil that is exceptionally free of contamination from modern human DNA. Direct high-throughput sequencing of a DNA extract from this fossil has thus far yielded over one million base pairs of hominoid nuclear DNA sequences. Comparison with the human and chimpanzee genomes reveals that modern human and Neanderthal DNA sequences diverged on average about 500,000 years ago. Existing technology and fossil resources are now sufficient to initiate a Neanderthal genome-sequencing effort.