Wellcome Trust news release – “Many people in the UK feel a strong sense of regional identity, and it now appears that there may be a scientific basis to this feeling, according to a landmark new study into the genetic makeup of the British Isles. An international team, led by researchers from the University of Oxford, UCL (University College London) and the Murdoch Childrens Research Institute in Australia, used DNA samples collected from more than 2,000 people to create the first fine-scale genetic map of any country in the world. Their findings, published in Nature, show that prior to the mass migrations of the 20th century there was a striking pattern of rich but subtle genetic variation across the UK, with distinct groups of genetically similar individuals clustered together geographically. By comparing this information with DNA samples from over 6,000 Europeans, the team was also able to identify clear traces of the population movements into the UK over the past 10,000 years. Their work confirmed, and in many cases shed further light on, known historical migration patterns.
Key findings
- There was not a single “Celtic” genetic group. In fact the Celtic parts of the UK (Scotland, Northern Ireland, Wales and Cornwall) are among the most different from each other genetically. For example, the Cornish are much more similar genetically to other English groups than they are to the Welsh or the Scots.
- There are separate genetic groups in Cornwall and Devon, with a division almost exactly along the modern county boundary.
- The majority of eastern, central and southern England is made up of a single, relatively homogeneous, genetic group with a significant DNA contribution from Anglo-Saxon migrations (10-40% of total ancestry). This settles a historical controversy in showing that the Anglo-Saxons intermarried with, rather than replaced, the existing populations.
- The population in Orkney emerged as the most genetically distinct, with 25% of DNA coming from Norwegian ancestors. This shows clearly that the Norse Viking invasion (9th century) did not simply replace the indigenous Orkney population.
- The Welsh appear more similar to the earliest settlers of Britain after the last ice age than do other people in the UK.
- There is no obvious genetic signature of the Danish Vikings, who controlled large parts of England (“The Danelaw”) from the 9th century.
- There is genetic evidence of the effect of the Landsker line – the boundary between English-speaking people in south-west Pembrokeshire (sometimes known as “Little England beyond Wales”) and the Welsh speakers in the rest of Wales, which persisted for almost a millennium.
- The analyses suggest there was a substantial migration across the channel after the original post-ice-age settlers, but before Roman times. DNA from these migrants spread across England, Scotland, and Northern Ireland, but had little impact in Wales.
- Many of the genetic clusters show similar locations to the tribal groupings and kingdoms around the end of the 6th century, after the settlement of the Anglo-Saxons, suggesting these tribes and kingdoms may have maintained a regional identity for many centuries.”
- Citation – UK mapped out by genetic ancestry. Finest-scale DNA survey of any country reveals historical migrations by Ewen Callaway, Corrected: .”
