Population studies use historical, archeological, linguistic, place-name and surname evidences to determine the ethnic origins of the people found in a specific region.
DNA tests now offer a more reliable way to confirm the previous hypothesis. Various research projects are under way, including several testing ancient or medieval DNA to see the genetic evolution of the studied population in time.
This thread aims at gathering and comparing the results and conclusions of each study available for Britain and Ireland. Here are a few links :
1) Excavating Past Population Structures by Surname-Based Sampling: The Genetic Legacy of the Vikings in Northwest England : aim at assessing the genetic impact of Norwegian Vikings in West Lancashire and the Wirral Peninsula. Comparison with samples from Norway, Orkney, the Shetlands, the Isle of Man, Cheshire, Anglesey, etc.
- Percentage of Scandinavian admixture in modern populations (average with other studies cited) : Anglesey (10%), Western Scotland (15%), Mid-Cheshire (21%), Western Isles and Skye (22.5%), Cumbria (37%), Wirral and West Lancashire (38%), Isle of Man (39%), Orkey (40%), Shetlands (42.5%).
- Comparison with medieval samples : Wirral (47%), West Lancashire (51%)
2) People of the British Isles : genetic comparison of the British population by region. The main purpose is medical, to create a map of genetic diseases in the UK. 3500 people tested in 30 different rural regions. The target date for collecting the sample is January 2009, so the final results won't be published before that.
3) Tracing the Phylogeography of Human Populations in Britain Based on 4th-11th Century mtDNA Genotypes : analysis of ancient and medieval British mtDNA samples to assess the importance of female migrations of Roman, Anglo-Saxon and Viking origin. Unfortunately, the conclusion isn't clear because of too limited samples. Results from Roman and early Saxon cemterries were merged under "Early Ancient" to add to the confusion.
4) Y Chromosome Evidence for Anglo-Saxon Mass Migration : attempts to find evidence of an Anglo-Saxon mass migration to central England (East Anglia and Midlands) by comparing Y-DNA haplotypes of Wales, central England, Friesland and Norway.
Conclusion : samples from central England and Friesland are almost undistinguishable. proving that a massive proportion of central English people descend from the Anglo-Saxons. Conversely, samples in North Wales and Norway were quite different.
5) Genetic evidence for different male and female roles in the British Isles : attempts to estimate the impact of successive migrations on the genetic make-up of Britain, by comparing the Y-DNA, mtDNA and X-chromosome in Wales, England and Orkney to Ireland, Norway, Friesland, the Basques (closet assumed descendent of the Paleolithic Europeans), the Anatolian Turks and Syrians (bothassociated with the source population of the Neolithic migrations).