著者

増田 隆一

出版者

北海道大学総合博物館

雑誌

北海道大学総合博物館研究報告 (ISSN:1348169X)

巻号頁・発行日

vol.6, pp.103-108, 2013-03

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Previous studies by our group have been summarized in this paper. To understand the genetic status of the Okhotsk people who lived in the southern coastal regions of the Okhotsk Sea between the fifth and twelfth centuries, nucleotide polymorphisms in hypervariable regions I and II (HVR I and HVR II) and the coding regions of mitochondrial DNA (mtDNA) were investigated. MtDNA haplogroups of the Okhotsk people examined were classified according to mtDNA lineages previously reported in northeastern Asians. The comparison of mtDNA haplogroup frequencies between the Okhotsk people and other Asian populations revealed that the genetic structures of the Okhotsk people are similar to those of populations currently living around the lower regions of the Amur River and the Ainu in Hokkaido. These results support our previous study on molecular phylogeny of only HVR I sequences in mtDNA (Sato et al. 2007), and strongly show that the Okhotsk people could have originated around lower regions of the Amur River and played the role of intermediate for gene flow from the continental-Sakhalin people to the Ainu (Sato et al. 2009a). To study further the genetic characteristics of the ancient people around Hokkaido, allele frequencies of the adenosine triphosphate-binding cassette sub-family C11 (ABCC11) gene, which determines the earwax phenotypes (dry or wet type), were analyzed. Interestingly, one homozygote for the 27-bp deletion in the ABCC11 gene was found first in the Epi-Jomon. Exact tests of people differentiation (including the previously reported data on modern people) showed that allele frequencies of the ABCC11 gene between the Jomon people and Ainu were significantly different statistically, whereas those between the Jomon and Epi- Jomon and those between the Epi-Jomon and Ainu were not significantly different. These results suggest that the Epi-Jomon people in Hokkaido were genetically affected by the Okhotsk people who possessed high frequency of allele A (recessive dry allele) of the ABCC11 locus (Sato et al. 2009b; Kazuta et al. 2011). On temporal genetic changes in ancient people of Hokkaido, the result of the ABCC11 analysis supports mtDNA haplogrouping.