Kanazawa team reconstructs high-coverage Jomon and Yayoi genomes from Japan

A Kanazawa University-led team reconstructed high-coverage genomes from two ancient people in Japan and reports the results in the Proceedings of the National Academy of Sciences, phys.org reported. IY1, a woman from the Initial Jomon period about 8,300 years ago, yielded roughly 67-fold genome-wide coverage. DO, a man from the Middle Yayoi period about 2,300 years ago, reached about 46-fold coverage despite poor DNA preservation in warm, humid, acidic soils. IY1 clustered with other Jomon individuals, supporting an early-diverging Jomon-related lineage in present-day Japanese ancestry. DO was closer to present-day mainland Japanese and carried Northeast Asia-linked components; mixture models pointed to continental proxies including Amur River, Inner Mongolia, and Shandong-related groups. Demographic analyses suggested ancestral declines around the Last Glacial Maximum, later growth in the Yayoi-related lineage, and relatively stable Jomon-related size. Both individuals carried relatively high amylase gene copy numbers, indicating starch-related genetic diversity before large-scale agriculture. DOI: 10.1073/pnas.2606162123.