File:Barrier analysis of European gene pool.png

English: Barrier analysis of European gene pool. The analysis was based upon great-circle coordinates of the cities where individual population samples were recruited and pair-wise Fst. The name of the city is indicated in the brackets in the left panel. Lower case letters point the order of the found barriers.

Using Barrier 2.2 software, we correlated geographic and genetic distances as measured by pair-wise Fst and great-circle coordinates of capitals or the city where an individual population sample had been recruited, respectively. The results overlapped with previous findings in that the first barrier was seen between Finland and all other samples, a second barrier separated Southern Italy from the remainder, a third was found between Western Russia, Poland and Lithuania on the one hand, and Bulgaria on the other, a fourth was seen between Kuusamo and Helsinki, and a fifth was between the Baltic region and Poland on the one hand, and Sweden on the other.

Barrier analysis revealed genetic barriers between Finland, Italy and other countries. Interestingly, barriers could be demonstrated within Finland (between Helsinki and Kuusamo) and Italy (between northern and southern part). Another barrier emerged between the Eastern Baltic region and Sweden, but not between the Eastern Baltic region and Poland. The barrier between Bulgaria and Western Russia, Poland and Lithuania may have arisen due to the fact that several populations are missing in between those countries. It has been shown previously that the populations of central European background are less differentiated genetically, whereas the Finns exhibit a more homogeneous population structure with decreased genetic diversity.