Researchers led by the University of Copenhagen's Jørgen Dissing report that they have isolated 1,000-year-old DNA from 10 Viking skeletons found at a burial site on the Danish island Funen. In PLoS ONE, Dissing and his colleagues describe how they removed the tooth samples with protective equipment -- before any archaeologists and anthropologists handled the remains -- and then carried out the pre-PCR steps in a clean lab. "The present work provides further evidence that retrieval of authentic DNA from ancient humans is indeed a possible undertaking provided adequate precautions are observed," write the authors.