Welsh and Cornish have purest British DNA

This year, attendees of the Royal Society's summer science exhibition in London will hear the results of an extensive DNA survey of Britain which will proclaim "that Welsh and Cornish people were among the most genetically distinct groups in the country."

The results will be presented by Peter Donnelly, professor of statistical science at Oxford University and director of the Wellcome Trust centre for human genetics, who believes that other areas of Britain contain a great deal of DNA from Viking raids and colonization from the 9th through 15th centuries.