Abstract
This study aimed to examine geographical associations of genetic factors (24 Y haplogroups, 10 autosomal ancestry components) with mean male height and the occurrence of lactose tolerance-associated alleles in a sample of 60 genetically interconnected Caucasian populations of Europe, the Near East, and North Africa. The results show that Y haplogroups or their combinations often match almost perfectly the geographical occurrence of a particular autosomal ancestry (correlation coefficients reaching up to r = 0.99), demonstrating that male founder effects played a crucial role in shaping population history. Male height adjusted for major environmental factors is positively related mainly to ancestry components BHG (Baltic hunter-gatherers), Villabruna, and Yamnaya, and the combined frequency of five Y haplogroups (I1, I2a-P37.2, N, Q, R1b-U106). The frequency of the European lactose tolerance-associated allele 13910*T correlates primarily with Yamnaya ancestry and with the combination of six Y haplogroups (I1, I2a-M223, Q, R1a, R1b-S116, R1b-U106), whereas the Near Eastern allele 13915*G is predicted by Natufian ancestry and three Y haplogroups typical of Arab populations (E1b-M123, J1, T). Of further note is the fact that country-level relationships between body height and ancestry components show both concordance and stark differences with genetic studies using individual-level relationships, which can potentially have important implications. In summary, many of the findings achieved are extremely impressive and their causality can often be inferred from already documented findings. Others offer hypotheses that could be tested with more sophisticated research.