Blood group B is a distinctly non-Indo-European blood type.
In Europe, only two areas with a high rate of blood group B
appear: one among the group of non-Indo-European peoples known
as the Finno-Ugrics (such as the Hungarians and the Finns),
the other among the central
Slavic peoples (Czechs, Southern Poles, and Northern Serbs).
The Viking invaders may have also had a relatively high
percentage of B gene, since many of the towns of Britain and
western Europe that are linked to the coast by internal lines
of communication such as large rivers, have a disproportional
amount of blood group B when compared to the surrounding territory.
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