Genetics reveal the origin story of East Asia’s favorite sweet bean

Genome sleuthing reveals that red beans were first domesticated in Japan, not China

A pile of red (adzuki) beans

Adzuki beans, which star in many East Asian desserts, were first domesticated in Japan 3,000 to 5,000 years ago.

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Tucked inside mochi, swirled into moon cakes or layered beneath custard in taiyaki, a sweet paste made from red beans is a beloved staple in East Asia.