“The distribution of HG 3 chromosomes is also strongly clinal, but with a very different axis and more on a regional scale…. It reaches its highest frequencies in central-eastern Europe, comprising approximately half of the chromosomes in the Russian, Polish, and Slovakian samples; frequencies in the southeast and southwest are low. This distribution resembles the third principal component of variation of classical gene frequencies, which has been interpreted by some geneticists (Cavalli-Sforza et al. 1994) as marking the movement, from north of the Caspian Sea, of the Kurgan people, dated to ~7,000 YBP.” More