The Jomon people themselves have no connection to Southeast Asia and are northern indigenous people

‌Reconstruction of the Jomon people of the archipelago 2,700 years ago, an ancient Asian race
They have no genetic connection to modern Japanese people
As genetics have advanced, it has been revealed that the Jomon genes possessed by modern Japanese people are related to the Jomon people of the Korean Peninsula
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And the ancient Asian races that lived in the Southeast Asian region are "Asian Black" people
The Negrito race discovered in northern Vietnam 3,600 years ago
They were either massacred or mixed with lineages that descended from southern China
It is said they hold about 5-10% in the current Southeast Asian gene pool
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Reconstruction of ancient bones discovered in the Devil's Cave in Primorsky Krai 8,000 years ago, Tungusic
The Tungusic people are one of the slight genetic ancestors of modern Japanese and Koreans, and they are also genetically related to the Ainu
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And the Ainu people
They are genetically close enough to be called the direct descendants of the Jomon people of the archipelago
They are a group that mixed with Siberian indigenous people who possess about 70% Jomon genes