Y-chromosomal binary haplogroups in the Japanese population and their relationship to 16 Y-STR polymorphisms. by Nonaka I, et al. Ann Hum Genet. 2007 Jul;71(Pt 4):480-95. Epub 2007 Feb 2.
Researchers investigated Y chromosomal binary and STR polymorphisms in 263 unrelated male individuals from the Japanese population, using 47 biallelic markers, they “distinguished 20 haplogroups, four of which (D2b1/-022457, O3/-002611*, O3/-LINE1 del, and O3/-021354*) were newly defined in this study. Most haplogroups in the Japanese population are found in one of the three major clades, C, D, or O. Among these, two major lineages, D2b and O2b, account for 66% of Japanese Y chromosomes. Haplotype diversity of binary markers was calculated at 86.3%. The addition of 16 Y-STR markers increased the number of haplotypes to 225, yielding a haplotype diversity of 99.40%.”