The most interesting new fact from this study: Estonia is a
small country with no geographic barriers and its Estonian
population is merely one million. In order to study the genetic
structure of Estonia in more detail, all Estonian individuals
were grouped here by their county of birth. Then, PCA was
performed and the mean values of the two first PC of the
counties were plotted onto the Estonian regional map (Figure 2).
Surprisingly, the resulting genetic map correlates almost
perfectly with the geographic map, although Estonia is only
43,400 km2 in size, and the mean area of a county only 2,900
km2. Thus, fine-scale genetic difference can be revealed by PC
analysis, and the results can be useful for identification of
the distant relatives.Figure 2 is reproduced here; the Estonian
map is on the bottom right. What seems very interesting is how
Swedes and Estonians both deviate towards Finns but from
different "starting points", a North German-Central European one
and Baltic-West Russian one respectively. This