There was a debate about haplogroup C. This haplogroup was the first that dispersed in Eurasia. It was found everywhere in Eurasia before the LGM. Thus before 20.000. But during the LGM humanity passed a major bottleneck and after it C disappears virtually everywhere replaced by J, I, R, G, O, Q, N, T, L. In East Europe after LGM there was zero C. While in pre LGM Moscow region it was frequent. C survived mostly in peripheral places like Australia, Papua, India in East Asian Amur region. One branch moved to America 6000 years ago as Na-Dene speakers (Apaches). But even in Amur region it was very rare before Middle Ages. The bulk of C2 we see in modern East Eurasia are due to Mongolian and Tungussic families expansions. Major founder effects. All this expansions occured in Middle Ages. Prior that the region was predominantly Q and N.