University of the Ryukyus

Graduate School of Science, The University of Tokyo

Summary of Presentations

The research team of Yoshie Koganebuchi, Assistant Professor at the Center for Advanced Medical Research, Faculty of Medicine, University of the Ryukyus (currently Graduate School of Science, The University of Tokyo), Masatoshi Matsunami, Assistant Professor, Minako Imamura, Associate Professor, Shiro Maeda, Professor Emeritus Professor Hajime Ishida and Professor Ryosuke Kimura at the Graduate School of Medicine, University of the Ryukyus, has published their research results in the Journal of Human Genetics Human Genetics.

In order to clarify the detailed population formation process of the people of the Ryukyu Islands, the research team analyzed the population genomes of 25 individuals from Okinawa Island and 25 individuals from the Miyako Islands, and confirmed that the people of Okinawa Island and the people of the Miyako Islands have different genetic backgrounds.

To explain the formation process of the present-day people of Okinawa Island and the Miyako Islands, the same Ryukyuan Jomon population could be assumed as the ancestor of both groups. Although migration from Honshu-Japan to the Ryukyu Islands is assumed to have occurred during the Gusuku period, the possibility of different rates of migration from Honshu-Japan between the ancestral groups of Okinawa and Miyako was suggested, confirming that the population structure existing within the present Miyako Islands can be explained by multiple inter-island migrations that occurred after the Gusuku period.

The results of this research will help clarify the complex history of the people of the Ryukyu Archipelago and unravel their past activities over East Asia.

Figure: Results of principal component analysis using whole genome sequence data. The horizontal axis shows the first principal component score and the vertical axis shows the second principal component score. Each point represents an individual, and the distance between points reflects genetic differences. In this figure, each regional population is color-coded. (A) Ryukyu Islands and East and Southeast Asian populations. (B) Han Chinese, Honshu, Okinawa, and Miyako populations.

For more information, please visit the University of the Ryukyus website.

Journals

Name of Journal	Journal of Human Genetics
Title of paper	Demographic history of Ryukyu islanders at the southern part of the Japanese Archipelago inferred from whole-genome resequencing data Demographic history of Ryukyu islanders at the southern part of the Japanese Archipelago inferred from whole-genome resequencing data)
DOI Number	10.1038/s10038-023-01180-y