The contribution of each haplogroup to the first and the second PCs are shown in gray. Population abbreviations are as follows: BeN, BeW, BeC, BeWP, BeEP, BeE – Belarusians from North, West, Central, West Polesie, East Polesie and East sub-regions, respectively, filled red circle denotes the total Belarusian population; RuS, RuC, RuN – Russians from southern, central and northern regions, respectively; Finns K – Finns from Karelia. K*(x N,P) refers to samples with M9, M20, M70 derived alleles and 92R7, M214 ancestral alleles; P*(xR) refers to samples with 92R7, M242 derived alleles and M207 ancestral allele; F*(xI,J,K) refers to samples with M89 derived allele and M9, M201, M170, 12f2 ancestral alleles; C(xF)DE refers to samples with Yap and M130 derived and M89 ancestral alleles. Frequencies of NRY haplogroups and references are listed in Table S3.