Japanese air attacks on the Mariana Islands 27 in preparation for operations against Japan itself. The USAAF bases in the Mariana Islands were within range of a number of Japanese air bases in the Pacific. These included Wake Island to the east, Truk and the Gilbert and Marshall Islands to the southeast, Woleai to the south and Yap to the southwest. To the north the Japanese had air bases in the Nampo Shoto chain of islands and Bonin Islands, which included three airstrips on Iwo Jima. Several of the minor islands in the Mariana chain also remained in Japanese hands, and there were airfields on Rota and
Japanese Americans 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. Also going back to the Jōmon, that gene is displayed in high frequencies in people of Japanese descent. The estimated percentage of this type of gene in Japanese Americans is about 34.7%. The highest frequencies occur in Okinawans and Hokkaidos. Overall, the genetic makeup of Japanese Americans show very mixed origins of genes, all due