94 per cent of Polynesian mtDNAs are of East Asian origin and only 6 per cent are of Melanesian origin

Genetic map

Genetic map


A new theory, based on DNA data argued, the “Polynesian” tribe split off from East Asia, 3500 years ago, not 17,000 years ago. The ‘Slow Boat’ model  – an origin in island Southeast Asia some 17,000 years ago, was not supported by the genetic evidence, reported the American Journal of Human Genetics, Volume 82, Issue 1, 194-198, 10 January 2008.
But yes, the Asia connection is strong: Polynesian genes contained a high proportion of Asian mtDNAs.  The  admixture occurred, approximately 3500 years ago, when the Polynesian evolved. The data suggested Ancestral Polynesian society was;
–  matrilocal in residence (men move to their wife’s land); and
–  matrilineal in descent (clans inherited through the mothers line.
Theory on gene mixing:  This admixture mostly involved:
–  Melanesian men (as evidenced by the high proportion of Melanesian Y chromosomes in Polynesia); and
– Asian women (as evidenced by the high proportion of Asian mtDNAs in Polynesia), an interesting finding that cannot be observed from the autosomal data.
Scenario analysis: This scenario is supported by suggestions of matrilineal descent and matrilocal residence in the ancient Polynesian society, and  which would therefore favor incorporation of Melanesian men rather than women into the ancestral Polynesian groups. About 94 per cent of Polynesian mtDNAs are of East Asian origin and only 6 per cent are of Melanesian origin (consisting of mainland New Guinea and surrounding islands, also known as Near Oceania), whereas 66 per cent of Polynesian Y chromosomes are of Melanesian origin and only 28 per cent are of East Asian origin.
Survey aimed to exclude European genes: Selected Polynesian samples for autosomal STR genotyping that do not carry European mtDNA or NRY haplogroups and whose self-described ancestry does not include any Europeans for at least two generations. Nonetheless, we cannot exclude some small amount of European admixture in these samples.
What was surveyed: The study genotyped 377 genome-wide distributed autosomal short tandem repeat (STR) loci in 47 Polynesians (10 Cook Islanders, 10 Tongans, 18 Samoans, 5 Tokelau Islanders, and 4 Nuie Islanders), 44 Han Chinese from Beijing, and 24 Papua New Guineans from the interior highlands (15 from the Eastern Highlands, 9 from the Southern Highlands) . The conclusion was East Asians and Melanesians represent the parental populations of Polynesians.
Hage and J. Marck, Matrilineality and the Melanesian origin of Polynesian Y chromosomes, Curr. Anthropol. 44 (2003), pp. 121127 and Genome-wide Analysis Indicates More Asian than Melanesian Ancestry of Polynesians The American Journal of Human Genetics, Volume 82, Issue 1, 194-198, 10 January 2008 http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B8JDD-4RHHD95-V&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=a8a05332f2b94077edbcf045244097a4

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