for National Geographic News
Using hairs from woolly mammoths, scientists have sequenced an extensive genome of these elephant cousins, a new report says.
The development brings researchers a step closer to "resurrecting" the extinct species via cloning, though so many technical obstacles stand in the way that some experts doubt it could ever happen.
(See "Mammoths to Return? DNA Advances Spur Resurrection Debate" [June 25, 2007].)
The study is said to be the first ever decoding of an extinct species' nuclear DNA, which contains vast amounts information.
Once interpreted, the genetic data will give researchers unprecedented access to the biology and evolution of woolly mammoths, which began dying out after the end of the last ice age, about 10,000 years ago.
"What our paper shows, for the first time, is that it is possible to sequence the genome of an extinct animal almost as well and as efficiently as a modern genome," said Stephan Schuster of Pennsylvania State University, one of the two project leaders.
The technique could be used to sequence the genomes of Neanderthals, and early humans—but not dinosaurs, which went extinct too long ago for their DNA to be viable today, according to the researchers.
Nuclear DNA resides in cell nuclei and is difficult to salvage from ancient bones. For one thing, it's far less plentiful than mitochondrial DNA, which is passed down only by mothers. The mitochondrial genome of the woolly mammoth was completely sequenced in 2006.
(Related: "Woolly Mammoth DNA Reveals Elephant Family Tree" [December 20, 2005].)
Nuclear DNA, however, carries much more genetic data, including just about all information about particular traits and physical characteristics.
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