Scientists use mammoth hair to sequence its DNA

By Agence France-Presse WASHINGTON--Scientists have sequenced the DNA in the hair of woolly mammoths dating back 50,000 years, paving the way to further research on many extinct species, according to a study published Thursday. "Hair shafts are a promising source of DNA," said the authors of the study from the University of Pennsylvania and the University of Copenhagen, published in the September 28 edition of Science. The research, which examined short fragments of mitochondrial DNA from the hair shafts of 13 Siberian mammoths stored in museum collections around the world, could open up vast new possibilities. "Long-term hair survival occurs in a variety of natural environments, and large quantities are present in taxonomic collections representing most extant, and many recently extinct" mammals, the authors wrote. The findings may "now allow us to add molecular-genetic data to the collections of Charles Darwin, Alexander von Humboldt and Carl von Linne," they added. Until now, researchers have relied on old bones as a source of DNA for extinct species. But this can lead to significant damage as bones have to be bored to remove cell samples. Old bones have also often been contaminated by bacteria over the centuries which can skew the results of any DNA sequencing. On the other hand, the DNA preserved in the keratine of a hair sample is often still perfectly intact. Hair samples can also be washed without altering their genetic make-up, the authors added. "The finding that DNA can be extracted from a specimen kept at room temperatures for two centuries puts a large number of collections stored in natural history museums within reach of molecular genomic analysis," the study adds. The technique, known as "sequencing-by-synthesis", sequenced the mitochondrial genomes of 13 woolly mammoths including the famous Adams mammoth which was discovered in the Siberian permafrost in 1779. After being excavated, the mammoth which is still the most complete skeleton of the creature ever found, has been stored at the Saint Petersburg Zoological Museum at room temperature for the past 200 years. Scientists now hope that with the data they have already collected they will be able to complete the whole DNA sequence of the woolly mammoth. The research could also be used to work out how and why some species died out.