Japan’s Ancestry Includes Third Group

Scientists at RIKEN in Japan analyzed genomes from over 3,200 people to reveal a previously unrecognized third ancestral group contributing to the Japanese population. For decades, research suggested Japanese people descended primarily from the Jomon hunter-gatherers and later migrants from East Asia. This new analysis supports a “tripartite origins” theory, linking the third group to the ancient Emishi people of northeastern Japan.

Researchers used whole-genome sequencing, offering about 3,000 times more data than older methods, and built a database called JEWEL linking genetic information to medical histories. They found Jomon ancestry strongest in Okinawa, roughly 28.5% of samples, and connections between western Japan and Han Chinese populations.

The study also identified 44 archaic DNA regions inherited from Neanderthals and Denisovans, some linked to conditions like diabetes and heart disease. While the findings expand understanding of Japanese population history, the researchers note a need for more genomic data from Asian populations to improve healthcare applications. The work continues as they seek to connect genetic differences to specific traits and diseases.