The TD of two groups of 15 STR haplotypes (except for DYS385a,b loci) found in the Kereys sub-clans demonstrates that TD value equal to 630 190 years (or approximately 21 6 generations) results when a mean of per-locus, per-generation mutation rate of 0.0033 and a 30-year generation time are used.
Это причем не мои слова а генетиков изучавших кереев