Genetics
In a recent study (2008) a joint analysis was performed for the first time on Swedish and Finnish autosomal genotypes. Swedish-speakers from Ostrobothnia (reference population of the study representing 40% of all Swedish-speakers in Finland) did not differ significantly from the neighbouring, adjacent Finnish-speaking populations but formed a genetic cluster with the Swedes only when a Swedish reference population was used, which highlights the significance of a proper reference population in comparative population genetics According to a recent Y-DNA study (2008), a Swedish-speaking reference group from Larsmo, Ostrobothnia, differed significantly from the Finnish-speaking sub-populations in the country in terms of Y-STR variation. This study however was comparing one small Swedish-speaking municipality of 4652 inhabitants to Finnish speaking provinces and only tells about the origin of two different Y-DNA haplotypes.
Read more about this topic: Swedish-speaking Population Of Finland