Русские и поляки-генетически одна популяция.

http://dienekes.blogspot.com/2008/11/european-population-structure-with-300k.html

Once again, it is clear that members of particular nations can mostly be mistaken for members of their closest neighbors. Almost all Spaniards are guessed as French; French mostly as Belgians but with sizable Spanish and UK minorities; UK as Belgians but with sizable French minorities; Norwegians mostly as Swedes but with some UK; Swedes mainly as Germans but many as Norwegians; most Poles as Russians, but some Slovaks or Czechs, and so on.

Русские покрывают поляков, как бык овцу:

http://narvasadataa.livejournal.com/2008/11/22/

 

Славянская генетика