An international team of geneticists and anthropologists has used bioinformatics to disentangle genetic evidence for the so-called land-bridge theory of how people first reached the Americas. The work may settle the debate over whether the Bering Strait was the gateway to the Americas or whether humans from Asia and the Pacific Islands reached the continent multiple times through prehistory as long ago as 30,000 years.

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"We have reasonably clear genetic evidence that the most likely candidate for the source of Native American populations is somewhere in east Asia [...] If there were a large number of migrations, and most of the source groups didn't have the variant, then we would not see the widespread presence of the mutation across the Americas."