Table 2 lists the pair-wise inflation factor λ between studied samples. The inflation factor λ was calculated with the method of the Genomic Control [19]. We assumed λ to be constant across the genome and λ was estimated as the median of the observed chi-square statistics divided by the median of the central chi-square distribution with 1 degree of freedom (i.e. 0.456). This factor was found to range from unity (between the samples from the same country) to 4.21 (between Spain and the Kuusamo region). The overall average λ value was 1.82; in separate clusters it amounted to 1.23 (Baltic Region, Western Russia and Poland), 1.54 (Italy and Spain), 1.22 (Central and Western Europe), and 1.86 (Finland), respectively. The correlation coefficient between geographic distance and λ was r2 = 0.386 (p-value≪0.01). This value is probably an underestimate of the European-wide relationship due to the inclusion of the Kuusamo and Geneva samples. One is an isolate and the other is a highly heterogeneous international metropolis. The λ values between CEU and the other samples (Table 2) were smaller than those obtained
