 People of Japanese descent show two pre-Yayoi ancestral Y chromosome lineages descended from Paleolithic people who had been isolated on the mainland of Japan.Studies of the mitochondrial component of Japanese American genes of haplogroup M12 shows a direct correlation of Japanese haplotypes with Tibetans.Other haplotypes that early descents of Japanese people were thought to be carried into include C-M8, which is another Y-chromosome haplotype.