Pleistocene park: Rebuilding the mammoth's genetic code has fired speculation that scientists may one day revive this species and other Ice Age beasts on the lines of Jurassic Park.
Credit: Wikimedia
PARIS: The draft genome of the woolly mammoth has been sequenced, opening the door to reconstructing a living mammoth by combining the sequence with elephant DNA.
The species became extinct at the end of the last Ice Age some 11,000 years ago.
The DNA for sequencing came from hair snipped from two mammoths preserved in Siberian permafrost for tens of thousands of years, scientists behind the breakthrough report today in the British journal Nature.
"50 per cent of the genome"
Important gaps in the picture remain, but even so, enough data is there to make a comparison between the woolly mammoth (Mammuthus primigenius) and its closest living relative, the elephant, they said.
The two species are so similar that their DNA differs by just 0.6 per cent, or about half the differences between humans and chimps.
The team, led by Stephan Schuster of Pennsylvania State University, notched up a first breakthrough last year by using mammoth hair to extract mitochondrial DNA, genetic material that is inherited from the female line.
The latest work focuses on nuclear DNA, or chromosome-bearing strands that have the most important protein-making software.
"We're sequencing random fragments and believe we have 50 per cent of the genome. We don't yet know the full size of the genome," said co-author Webb Miller.
Giant step forward
The hair technique marks a giant step forward compared to the previous method, which consisted of teasing DNA out from bone marrow in the remains of frozen marrow. DNA of this kind can be badly damaged by bouts of freeze-thaw over the millennia, enabling water and bacteria to enter through porous bones.
But the keratin sheath of hair provided a surprisingly good shield for the DNA inside, said Miller.
The two mammoths from which the hair shafts were taken died around 20,000 years and 50,000 years ago respectively.
In addition to the new source for gene sequencing, the scientists have harnessed new technology that can unravel DNA code in a fraction of the time it took a few years ago.
Rebuilding the mammoth's genetic code has fired speculation that scientists may one day revive this species and other Ice Age beasts on the lines of the Hollywood movie Jurassic Park (see, Back from the dead, Cosmos Online).
