Y-DNA vs. genome-wide ancestry in Poles, Germans and Scandinavians

The two MDS plots below (main and inset) were based on very different data and methods, and yet they look strikingly similar. But frequencies of Y-chromosome and genome-wide markers are affected by similar factors, such as geography, topography, language and culture, so it's not really all that surprising.

However, the MDS plot from Y-STR data clearly shows greater distances between the ethnic groups, and I think that's due to the fact that languages and cultures in North-Central Europe were spread by highly patriarchal and patrilineal groups, like the early Slavs. When these groups expanded, they often drove out or killed males from other cultures, and absorbed the women. Hence, that's one of the reasons why results from genome-wide markers usually won't show perfect correlation with those from Y-chromosome data.

Polish, German, Swedish and Danish project members can check their positions on the main plot above by looking here.

See also...

Y-DNA of West Slavs vs. Eastern Germans (aka. German Sorbs more Slavic than Poles...or so it seems)

Reference...

Rebala et al., Contemporary paternal genetic landscape of Polish and German populations: from early medieval Slavic expansion to post-World War II resettlements, European Journal of Human Genetics advance online publication 12 September 2012; doi: 10.1038/ejhg.2012.190