3) Central and Western Europe, and 4) Italy, with the southern Italians being more “distant” (Figure 2). PC analysis of the 1,026 Estonians revealed the fine-structure of this population, with the first two PCs describing 1.9% and 1.5% of the genetic variance, respectively. The spread of Estonian individuals is relatively wide as the subregions overlap on individual level, but the median value of PCs, calculated for each county show a remarkable correlation with the regional map of Estonian geography (Figures 2 and S1). PC analysis of genome-wide SNP genotypes is therefore capable of highlighting both global and minute intra-population genetic differences (Figure 2).
