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Ancient voyaging and Polynesian origins.

ABSTRACT: The "Polynesian motif" defines a lineage of human mtDNA that is restricted to Austronesian-speaking populations and is almost fixed in Polynesians. It is widely thought to support a rapid dispersal of maternal lineages from Taiwan ~4000 years ago (4 ka), but the chronological resolution of existing control-region data is poor, and an East Indonesian origin has also been proposed. By analyzing 157 complete mtDNA genomes, we show that the motif itself most likely originated >6 ka in the vicinity of the Bismarck Archipelago, and its immediate ancestor is >8 ka old and virtually restricted to Near Oceania. This indicates that Polynesian maternal lineages from Island Southeast Asia gained a foothold in Near Oceania much earlier than dispersal from either Taiwan or Indonesia 3-4 ka would predict. However, we find evidence in minor lineages for more recent two-way maternal gene flow between Island Southeast Asia and Near Oceania, likely reflecting movements along a "voyaging corridor" between them, as previously proposed on archaeological grounds. Small-scale mid-Holocene movements from Island Southeast Asia likely transmitted Austronesian languages to the long-established Southeast Asian colonies in the Bismarcks carrying the Polynesian motif, perhaps also providing the impetus for the expansion into Polynesia.

SUBMITTER: Soares P

PROVIDER: S-EPMC3035714 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Ancient voyaging and Polynesian origins.

Soares Pedro P Rito Teresa T Trejaut Jean J Mormina Maru M Hill Catherine C Tinkler-Hundal Emma E Braid Michelle M Clarke Douglas J DJ Loo Jun-Hun JH Thomson Noel N Denham Tim T Donohue Mark M Macaulay Vincent V Lin Marie M Oppenheimer Stephen S Richards Martin B MB

American journal of human genetics 20110203 2

The "Polynesian motif" defines a lineage of human mtDNA that is restricted to Austronesian-speaking populations and is almost fixed in Polynesians. It is widely thought to support a rapid dispersal of maternal lineages from Taiwan ~4000 years ago (4 ka), but the chronological resolution of existing control-region data is poor, and an East Indonesian origin has also been proposed. By analyzing 157 complete mtDNA genomes, we show that the motif itself most likely originated >6 ka in the vicinity o ...[more]

PMID: 21295281

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Ancient voyaging and Polynesian origins.

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Ancient voyaging and Polynesian origins.

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