Pair-wise LD between SNPs was measured by means of the r2 statistics (see Methods). Genome-wide, average r2 ranged from 0.24 to 0.28 at smaller distances (5 kb), and decreased to between 0.05 and 0.07 at larger distances (100 kb), depending upon population. Above 75 kb the cohorts started to diverge reflecting the LD extinction towards the north (Figure 1), although the difference was not statistically significant (one-tailed t-test, p-value≤0.05 was considered as statistically significant).
