Genetics University of Manchester
The Romans, Vikings and Normans may have ruled or invaded the British for hundreds of years, but they left barely a trace on our DNA, the first detailed study of the genetics of British people has revealed.
The analysis shows that the Anglo-Saxons were the only conquering force, around 400-500 AD, to substantially alter the country’s genetic makeup, with most white British people now owing almost 30% of their DNA to the ancestors of modern-day Germans.
People living in southern and central England today typically share about 40% of their DNA with the French, 11% with the Danes and 9% with the Belgians, the study of more than 2, 000 people found. The French contribution was not linked to the Norman invasion of 1066, however, but a previously unknown wave of migration to Britain some time after then end of the last Ice Age nearly 10, 000 years ago.
Prof Peter Donnelly, director of the Wellcome Trust Centre for Human Genetics at the University of Oxford, who co-led the research, said: “It has long been known that human populations differ genetically, but never before have we been able to observe such exquisite and fascinating detail.”Map of the UK showing clustering of individuals based on genetics, and its striking relationship with geography. Photograph: Stephen Leslie/Nature/EuroGeographics
The population of the Orkney Isles was found to be the most genetically distinct, with 25% of DNA coming from Norwegian ancestors who invaded the islands in the 9th century.
The Welsh also showed striking differences to the rest of Britain, and scientists concluded that their DNA most closely resembles that of the earliest hunter-gatherers to have arrived when Britain became habitable again after the Ice Age.
“The Celtic regions one might have expected to be genetically similar, but they’re among the most different in our study, ” said Mark Robinson, an archaeologist from the Oxford University Museum of Natural History and a co-author. “It’s stressing their genetic difference, it’s not saying there aren’t cultural similarities.”
The study, published on Wednesday in the journal Nature, is the culmination of 20 years of work. Scientists began collecting DNA samples from people in Orkney in 1994 and gradually worked across most of the British Isles.
The participants were all white British, lived in rural areas and had four grandparents all born within 50 miles (80km) of each other. Since a quarter of our genome comes from each of our grandparents, the scientists were effectively obtaining a snapshot of British genetics at at the beginning of the 20th century.
Sir Walter Bodmer, of the University of Oxford, who conceived the study, said: “We’re reaching back in time to before most of the mixing of the population, which would fog history.”
The team also looked at data from 6, 209 individuals from 10 European countries to reconstruct the contributions their ancestors made to the genetic makeup of the British.