BEIJING, Sept. 29 (Xinhuanet) -- A new study shows mammoths' hair is a better source of ancient DNA than bone or muscle, and may help scientists to learn more about the extinct creatures, according to a report in Friday's Science.

    For years, researchers are trying to sequence the mammoth's DNA from its frozen remains, but their efforts have been complicated by contamination.

    The report suggested that mammoth hair seems to be an excellent source of well-preserved DNA.

    "The main problem with things like bone is that it contains real DNA from the source, but also a load of DNA that is undesirable," said study team member Tom Gilbert of the University of Copenhagen. "For example, when a mammoth dies and the body starts putrefying, bacteria gets all throughout the body. Later, as it's buried in the ground, soil bacteria get into it."

    Contamination from bacteria DNA generally make up 50 to more than 90 percent of the raw DNA extracted from the bone and muscles of ancient specimens, Gilbert said. In contrast, more than 90 percent of the DNA extracted from hairs taken from woolly mammoth specimens in the new study belonged to the extinct mega-mammals themselves.

    Keratin, the hard covering of hair, could protect the DNA, explained lead researcher Stephan C. Schuster of Penn State University. Hair also can more easily be cleaned of contaminants such as bacteria.

    "We plan to use hair and other keratin-containing body parts, such as nail and horn, to untangle the secrets of populations that lived long ago, so these populations can send a message from the past about what it might have taken for them to survive," Schuster said. "This discovery is good news for anyone interested in learning more about how species of large mammals can go extinct."

    The researchers obtained hair from 10 woolly mammoth fossils discovered in northern Siberia ranged in age from 50,000 to 12,000 years old. One of the samples came from the famous Adams mammoth discovered in 1799 and stored in a Russian museum for 200 years at room temperature -- far from ideal conditions for DNA preservation.

    Schuster said learning the DNA sequence does not mean that the ancient animal can be cloned or somehow resurrected, adding "this is science fiction."

    (Agencies)