Polynesian

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform

Mark Stoneking - One of the best experts on this subject based on the ideXlab platform.

  • Genome-wide analysis indicates more Asian than Melanesian ancestry of Polynesians.
    American journal of human genetics, 2008
    Co-Authors: Manfred Kayser, Silke Brauer, Oscar Lao, Kathrin Saar, Xingyu Wang, Peter Nürnberg, Ronald J. Trent, Mark Stoneking
    Abstract:

    Analyses of mitochondrial DNA (mtDNA) and nonrecombining Y chromosome (NRY) variation in the same populations are sometimes concordant but sometimes discordant. Perhaps the most dramatic example known of the latter concerns Polynesians, in which about 94% of Polynesian mtDNAs are of East Asian origin, while about 66% of Polynesian Y chromosomes are of Melanesian origin. Here we analyze on a genome-wide scale, to our knowledge for the first time, the origins of the autosomal gene pool of Polynesians by screening 377 autosomal short tandem repeat (STR) loci in 47 Pacific Islanders and compare the results with those obtained from 44 Chinese and 24 individuals from Papua New Guinea. Our data indicate that on average about 79% of the Polynesian autosomal gene pool is of East Asian origin and 21% is of Melanesian origin. The genetic data thus suggest a dual origin of Polynesians with a high East Asian but also considerable Melanesian component, reflecting sex-biased admixture in Polynesian history in agreement with the Slow Boat model. More generally, these results also demonstrate that conclusions based solely on uniparental markers, which are frequently used in population history studies, may not accurately reflect the history of the autosomal gene pool of a population.

  • Melanesian origin of Polynesian Y-chromosomes
    Current biology : CB, 2000
    Co-Authors: Manfred Kayser, Silke Brauer, Gunter Weiss, Peter A Underhill, Lutz Roewer, Wulf Schiefenhovel, Mark Stoneking
    Abstract:

    Two competing hypotheses for the origins of Polynesians are the 'express-train' model, which supposes a recent and rapid expansion of Polynesian ancestors from Asia/Taiwan via coastal and island Melanesia, and the 'entangled-bank' model, which supposes a long history of cultural and genetic interactions among Southeast Asians, Melanesians and Polynesians. Most genetic data, especially analyses of mitochondrial DNA (mtDNA) variation, support the express-train model, as does linguistic and archaeological evidence. Here, we used Y-chromosome polymorphisms to investigate the origins of Polynesians. We analysed eight single nucleotide polymorphisms (SNPs) and seven short tandem repeat (STR) loci on the Y chromosome in 28 Cook Islanders from Polynesia and 583 males from 17 Melanesian, Asian and Australian populations. We found that all Polynesians belong to just three Y-chromosome haplotypes, as defined by unique event polymorphisms. The major Y haplotype in Polynesians (82% frequency) was restricted to Melanesia and eastern Indonesia and most probably arose in Melanesia. Coalescence analysis of associated Y-STR haplotypes showed evidence of a population expansion in Polynesians, beginning about 2,200 years ago. The other two Polynesian Y haplotypes were widespread in Asia but were also found in Melanesia. All Polynesian Y chromosomes can be traced back to Melanesia, although some of these Y-chromosome types originated in Asia. Together with other genetic and cultural evidence, we propose a new model of Polynesian origins that we call the 'slow-boat' model: Polynesian ancestors did originate from Asia/Taiwan but did not move rapidly through Melanesia; rather, they interacted with and mixed extensively with Melanesians, leaving behind their genes and incorporating many Melanesian genes before colonising the Pacific.

  • melanesian origin of Polynesian y chromosomes
    Current Biology, 2000
    Co-Authors: Manfred Kayser, Silke Brauer, Gunter Weiss, Peter A Underhill, Lutz Roewer, Wulf Schiefenhovel, Mark Stoneking
    Abstract:

    Results: We analysed eight single nucleotide polymorphisms (SNPs) and seven short tandem repeat (STR) loci on the Y chromosome in 28 Cook Islanders from Polynesia and 583 males from 17 Melanesian, Asian and Australian populations. We found that all Polynesians belong to just three Y-chromosome haplotypes, as defined by unique event polymorphisms. The major Y haplotype in Polynesians (82% frequency) was restricted to Melanesia and eastern Indonesia and most probably arose in Melanesia. Coalescence analysis of associated Y-STR haplotypes showed evidence of a population expansion in Polynesians, beginning about 2,200 years ago. The other two Polynesian Y haplotypes were widespread in Asia but were also found in Melanesia. Conclusions: All Polynesian Y chromosomes can be traced back to Melanesia, although some of these Y-chromosome types originated in Asia. Together with other genetic and cultural evidence, we propose a new model of Polynesian origins that we call the ‘slow-boat’ model: Polynesian ancestors did originate from Asia/Taiwan but did not move rapidly through Melanesia; rather, they interacted with and mixed extensively with Melanesians, leaving behind their genes and incorporating many Melanesian genes before colonising the Pacific.

  • Polynesian genetic affinities with Southeast Asian populations as identified by mtDNA analysis.
    American journal of human genetics, 1995
    Co-Authors: Terry Melton, Nilmani Saha, R. Peterson, A. J. Redd, Abdul Salam M. Sofro, J. J. Martinson, Mark Stoneking
    Abstract:

    Polynesian genetic affinities to populations of Asia were studied using mtDNA markers. A total of 1,037 individuals from 12 populations were screened for a 9-bp deletion in the intergenic region between the COII and tRNA(Lys) genes that approaches fixation in Polynesians. Sequence-specific oligonucleotide probes that identify specific mtDNA control region nucleotide substitutions were used to describe variation in individuals with the 9-bp deletion. The 9-bp deletion was not observed in northern Indians, Bangladeshis, or Pakistanis but was seen at low to moderate frequencies in the nine other Southeast Asian populations. Three substitutions in the control region at positions 16217, 16247, and 16261 have previously been observed at high frequency in Polynesian mtDNAs; this "Polynesian motif" was observed in 20% of east Indonesians with the 9-bp deletion but was observed in only one additional individual. mtDNA types related to the Polynesian motif are highest in frequency in the corridor from Taiwan south through the Philippines and east Indonesia, and the highest diversity for these types is in Taiwan. These results are consistent with linguistic evidence of a Taiwanese origin for the proto-Polynesian expansion, which spread throughout Oceania by way of Indonesia.

Manfred Kayser - One of the best experts on this subject based on the ideXlab platform.

  • Genome-wide analysis indicates more Asian than Melanesian ancestry of Polynesians.
    American journal of human genetics, 2008
    Co-Authors: Manfred Kayser, Silke Brauer, Oscar Lao, Kathrin Saar, Xingyu Wang, Peter Nürnberg, Ronald J. Trent, Mark Stoneking
    Abstract:

    Analyses of mitochondrial DNA (mtDNA) and nonrecombining Y chromosome (NRY) variation in the same populations are sometimes concordant but sometimes discordant. Perhaps the most dramatic example known of the latter concerns Polynesians, in which about 94% of Polynesian mtDNAs are of East Asian origin, while about 66% of Polynesian Y chromosomes are of Melanesian origin. Here we analyze on a genome-wide scale, to our knowledge for the first time, the origins of the autosomal gene pool of Polynesians by screening 377 autosomal short tandem repeat (STR) loci in 47 Pacific Islanders and compare the results with those obtained from 44 Chinese and 24 individuals from Papua New Guinea. Our data indicate that on average about 79% of the Polynesian autosomal gene pool is of East Asian origin and 21% is of Melanesian origin. The genetic data thus suggest a dual origin of Polynesians with a high East Asian but also considerable Melanesian component, reflecting sex-biased admixture in Polynesian history in agreement with the Slow Boat model. More generally, these results also demonstrate that conclusions based solely on uniparental markers, which are frequently used in population history studies, may not accurately reflect the history of the autosomal gene pool of a population.

  • Melanesian origin of Polynesian Y-chromosomes
    Current biology : CB, 2000
    Co-Authors: Manfred Kayser, Silke Brauer, Gunter Weiss, Peter A Underhill, Lutz Roewer, Wulf Schiefenhovel, Mark Stoneking
    Abstract:

    Two competing hypotheses for the origins of Polynesians are the 'express-train' model, which supposes a recent and rapid expansion of Polynesian ancestors from Asia/Taiwan via coastal and island Melanesia, and the 'entangled-bank' model, which supposes a long history of cultural and genetic interactions among Southeast Asians, Melanesians and Polynesians. Most genetic data, especially analyses of mitochondrial DNA (mtDNA) variation, support the express-train model, as does linguistic and archaeological evidence. Here, we used Y-chromosome polymorphisms to investigate the origins of Polynesians. We analysed eight single nucleotide polymorphisms (SNPs) and seven short tandem repeat (STR) loci on the Y chromosome in 28 Cook Islanders from Polynesia and 583 males from 17 Melanesian, Asian and Australian populations. We found that all Polynesians belong to just three Y-chromosome haplotypes, as defined by unique event polymorphisms. The major Y haplotype in Polynesians (82% frequency) was restricted to Melanesia and eastern Indonesia and most probably arose in Melanesia. Coalescence analysis of associated Y-STR haplotypes showed evidence of a population expansion in Polynesians, beginning about 2,200 years ago. The other two Polynesian Y haplotypes were widespread in Asia but were also found in Melanesia. All Polynesian Y chromosomes can be traced back to Melanesia, although some of these Y-chromosome types originated in Asia. Together with other genetic and cultural evidence, we propose a new model of Polynesian origins that we call the 'slow-boat' model: Polynesian ancestors did originate from Asia/Taiwan but did not move rapidly through Melanesia; rather, they interacted with and mixed extensively with Melanesians, leaving behind their genes and incorporating many Melanesian genes before colonising the Pacific.

  • melanesian origin of Polynesian y chromosomes
    Current Biology, 2000
    Co-Authors: Manfred Kayser, Silke Brauer, Gunter Weiss, Peter A Underhill, Lutz Roewer, Wulf Schiefenhovel, Mark Stoneking
    Abstract:

    Results: We analysed eight single nucleotide polymorphisms (SNPs) and seven short tandem repeat (STR) loci on the Y chromosome in 28 Cook Islanders from Polynesia and 583 males from 17 Melanesian, Asian and Australian populations. We found that all Polynesians belong to just three Y-chromosome haplotypes, as defined by unique event polymorphisms. The major Y haplotype in Polynesians (82% frequency) was restricted to Melanesia and eastern Indonesia and most probably arose in Melanesia. Coalescence analysis of associated Y-STR haplotypes showed evidence of a population expansion in Polynesians, beginning about 2,200 years ago. The other two Polynesian Y haplotypes were widespread in Asia but were also found in Melanesia. Conclusions: All Polynesian Y chromosomes can be traced back to Melanesia, although some of these Y-chromosome types originated in Asia. Together with other genetic and cultural evidence, we propose a new model of Polynesian origins that we call the ‘slow-boat’ model: Polynesian ancestors did originate from Asia/Taiwan but did not move rapidly through Melanesia; rather, they interacted with and mixed extensively with Melanesians, leaving behind their genes and incorporating many Melanesian genes before colonising the Pacific.

Silke Brauer - One of the best experts on this subject based on the ideXlab platform.

  • Genome-wide analysis indicates more Asian than Melanesian ancestry of Polynesians.
    American journal of human genetics, 2008
    Co-Authors: Manfred Kayser, Silke Brauer, Oscar Lao, Kathrin Saar, Xingyu Wang, Peter Nürnberg, Ronald J. Trent, Mark Stoneking
    Abstract:

    Analyses of mitochondrial DNA (mtDNA) and nonrecombining Y chromosome (NRY) variation in the same populations are sometimes concordant but sometimes discordant. Perhaps the most dramatic example known of the latter concerns Polynesians, in which about 94% of Polynesian mtDNAs are of East Asian origin, while about 66% of Polynesian Y chromosomes are of Melanesian origin. Here we analyze on a genome-wide scale, to our knowledge for the first time, the origins of the autosomal gene pool of Polynesians by screening 377 autosomal short tandem repeat (STR) loci in 47 Pacific Islanders and compare the results with those obtained from 44 Chinese and 24 individuals from Papua New Guinea. Our data indicate that on average about 79% of the Polynesian autosomal gene pool is of East Asian origin and 21% is of Melanesian origin. The genetic data thus suggest a dual origin of Polynesians with a high East Asian but also considerable Melanesian component, reflecting sex-biased admixture in Polynesian history in agreement with the Slow Boat model. More generally, these results also demonstrate that conclusions based solely on uniparental markers, which are frequently used in population history studies, may not accurately reflect the history of the autosomal gene pool of a population.

  • Melanesian origin of Polynesian Y-chromosomes
    Current biology : CB, 2000
    Co-Authors: Manfred Kayser, Silke Brauer, Gunter Weiss, Peter A Underhill, Lutz Roewer, Wulf Schiefenhovel, Mark Stoneking
    Abstract:

    Two competing hypotheses for the origins of Polynesians are the 'express-train' model, which supposes a recent and rapid expansion of Polynesian ancestors from Asia/Taiwan via coastal and island Melanesia, and the 'entangled-bank' model, which supposes a long history of cultural and genetic interactions among Southeast Asians, Melanesians and Polynesians. Most genetic data, especially analyses of mitochondrial DNA (mtDNA) variation, support the express-train model, as does linguistic and archaeological evidence. Here, we used Y-chromosome polymorphisms to investigate the origins of Polynesians. We analysed eight single nucleotide polymorphisms (SNPs) and seven short tandem repeat (STR) loci on the Y chromosome in 28 Cook Islanders from Polynesia and 583 males from 17 Melanesian, Asian and Australian populations. We found that all Polynesians belong to just three Y-chromosome haplotypes, as defined by unique event polymorphisms. The major Y haplotype in Polynesians (82% frequency) was restricted to Melanesia and eastern Indonesia and most probably arose in Melanesia. Coalescence analysis of associated Y-STR haplotypes showed evidence of a population expansion in Polynesians, beginning about 2,200 years ago. The other two Polynesian Y haplotypes were widespread in Asia but were also found in Melanesia. All Polynesian Y chromosomes can be traced back to Melanesia, although some of these Y-chromosome types originated in Asia. Together with other genetic and cultural evidence, we propose a new model of Polynesian origins that we call the 'slow-boat' model: Polynesian ancestors did originate from Asia/Taiwan but did not move rapidly through Melanesia; rather, they interacted with and mixed extensively with Melanesians, leaving behind their genes and incorporating many Melanesian genes before colonising the Pacific.

  • melanesian origin of Polynesian y chromosomes
    Current Biology, 2000
    Co-Authors: Manfred Kayser, Silke Brauer, Gunter Weiss, Peter A Underhill, Lutz Roewer, Wulf Schiefenhovel, Mark Stoneking
    Abstract:

    Results: We analysed eight single nucleotide polymorphisms (SNPs) and seven short tandem repeat (STR) loci on the Y chromosome in 28 Cook Islanders from Polynesia and 583 males from 17 Melanesian, Asian and Australian populations. We found that all Polynesians belong to just three Y-chromosome haplotypes, as defined by unique event polymorphisms. The major Y haplotype in Polynesians (82% frequency) was restricted to Melanesia and eastern Indonesia and most probably arose in Melanesia. Coalescence analysis of associated Y-STR haplotypes showed evidence of a population expansion in Polynesians, beginning about 2,200 years ago. The other two Polynesian Y haplotypes were widespread in Asia but were also found in Melanesia. Conclusions: All Polynesian Y chromosomes can be traced back to Melanesia, although some of these Y-chromosome types originated in Asia. Together with other genetic and cultural evidence, we propose a new model of Polynesian origins that we call the ‘slow-boat’ model: Polynesian ancestors did originate from Asia/Taiwan but did not move rapidly through Melanesia; rather, they interacted with and mixed extensively with Melanesians, leaving behind their genes and incorporating many Melanesian genes before colonising the Pacific.

Peter A Underhill - One of the best experts on this subject based on the ideXlab platform.

  • increased y chromosome resolution of haplogroup o suggests genetic ties between the ami aborigines of taiwan and the Polynesian islands of samoa and tonga
    Gene, 2012
    Co-Authors: Sheyla Mirabal, Peter A Underhill, Kristian J Herrera, Tenzin Gayden, Maria Regueiro, Ralph Garciabertrand, Rene J Herrera
    Abstract:

    The Austronesian expansion has left its fingerprint throughout two thirds of the circumference of the globe reaching the island of Madagascar in East Africa to the west and Easter Island, off the coast of Chile, to the east. To date, several theories exist to explain the current genetic distribution of Austronesian populations, with the "slow boat" model being the most widely accepted, though other conjectures (i.e., the "express train" and "entangled bank" hypotheses) have also been widely discussed. In the current study, 158 Y chromosomes from the Polynesian archipelagos of Samoa and Tonga were typed using high resolution binary markers and compared to populations across Mainland East Asia, Taiwan, Island Southeast Asia, Melanesia and Polynesia in order to establish their patrilineal genetic relationships. Y-STR haplotypes on the C2 (M38), C2a (M208), O1a (M119), O3 (M122) and O3a2 (P201) backgrounds were utilized in an attempt to identify the differing sources of the current Y-chromosomal haplogroups present throughout Polynesia (of Melanesian and/or Asian descent). We find that, while haplogroups C2a, S and K3-P79 suggest a Melanesian component in 23%-42% of the Samoan and Tongan Y chromosomes, the majority of the paternal Polynesian gene pool exhibits ties to East Asia. In particular, the prominence of sub-haplogroup O3a2c* (P164), which has previously been observed at only minimal levels in Mainland East Asians (2.0-4.5%), in both Polynesians (ranging from 19% in Manua to 54% in Tonga) and Ami aborigines from Taiwan (37%) provides, for the first time, evidence for a genetic connection between the Polynesian populations and the Ami.

  • Melanesian origin of Polynesian Y-chromosomes
    Current biology : CB, 2000
    Co-Authors: Manfred Kayser, Silke Brauer, Gunter Weiss, Peter A Underhill, Lutz Roewer, Wulf Schiefenhovel, Mark Stoneking
    Abstract:

    Two competing hypotheses for the origins of Polynesians are the 'express-train' model, which supposes a recent and rapid expansion of Polynesian ancestors from Asia/Taiwan via coastal and island Melanesia, and the 'entangled-bank' model, which supposes a long history of cultural and genetic interactions among Southeast Asians, Melanesians and Polynesians. Most genetic data, especially analyses of mitochondrial DNA (mtDNA) variation, support the express-train model, as does linguistic and archaeological evidence. Here, we used Y-chromosome polymorphisms to investigate the origins of Polynesians. We analysed eight single nucleotide polymorphisms (SNPs) and seven short tandem repeat (STR) loci on the Y chromosome in 28 Cook Islanders from Polynesia and 583 males from 17 Melanesian, Asian and Australian populations. We found that all Polynesians belong to just three Y-chromosome haplotypes, as defined by unique event polymorphisms. The major Y haplotype in Polynesians (82% frequency) was restricted to Melanesia and eastern Indonesia and most probably arose in Melanesia. Coalescence analysis of associated Y-STR haplotypes showed evidence of a population expansion in Polynesians, beginning about 2,200 years ago. The other two Polynesian Y haplotypes were widespread in Asia but were also found in Melanesia. All Polynesian Y chromosomes can be traced back to Melanesia, although some of these Y-chromosome types originated in Asia. Together with other genetic and cultural evidence, we propose a new model of Polynesian origins that we call the 'slow-boat' model: Polynesian ancestors did originate from Asia/Taiwan but did not move rapidly through Melanesia; rather, they interacted with and mixed extensively with Melanesians, leaving behind their genes and incorporating many Melanesian genes before colonising the Pacific.

  • melanesian origin of Polynesian y chromosomes
    Current Biology, 2000
    Co-Authors: Manfred Kayser, Silke Brauer, Gunter Weiss, Peter A Underhill, Lutz Roewer, Wulf Schiefenhovel, Mark Stoneking
    Abstract:

    Results: We analysed eight single nucleotide polymorphisms (SNPs) and seven short tandem repeat (STR) loci on the Y chromosome in 28 Cook Islanders from Polynesia and 583 males from 17 Melanesian, Asian and Australian populations. We found that all Polynesians belong to just three Y-chromosome haplotypes, as defined by unique event polymorphisms. The major Y haplotype in Polynesians (82% frequency) was restricted to Melanesia and eastern Indonesia and most probably arose in Melanesia. Coalescence analysis of associated Y-STR haplotypes showed evidence of a population expansion in Polynesians, beginning about 2,200 years ago. The other two Polynesian Y haplotypes were widespread in Asia but were also found in Melanesia. Conclusions: All Polynesian Y chromosomes can be traced back to Melanesia, although some of these Y-chromosome types originated in Asia. Together with other genetic and cultural evidence, we propose a new model of Polynesian origins that we call the ‘slow-boat’ model: Polynesian ancestors did originate from Asia/Taiwan but did not move rapidly through Melanesia; rather, they interacted with and mixed extensively with Melanesians, leaving behind their genes and incorporating many Melanesian genes before colonising the Pacific.

  • Polynesian origins: Insights from the Y chromosome
    Proceedings of the National Academy of Sciences of the United States of America, 2000
    Co-Authors: Li Jin, Peter A Underhill, Jeremy J. Martinson, Nilmani Saha, Stephen T. Mcgarvey, Mark D. Shriver, Jiayou Chu, Peter J. Oefner, Ranajit Chakraborty
    Abstract:

    The question surrounding the colonization of Polynesia has remained controversial. Two hypotheses, one postulating Taiwan as the putative homeland and the other asserting a Melanesian origin of the Polynesian people, have received considerable attention. In this work, we present haplotype data based on the distribution of 19 biallelic polymorphisms on the Y chromosome in a sample of 551 male individuals from 36 populations living in Southeast Asia, Taiwan, Micronesia, Melanesia, and Polynesia. Surprisingly, nearly none of the Taiwanese Y haplotypes were found in Micronesia and Polynesia. Likewise, a Melanesian-specific haplotype was not found among the Polynesians. However, all of the Polynesian, Micronesian, and Taiwanese haplotypes are present in the extant Southeast Asian populations. Evidently, the Y-chromosome data do not lend support to either of the prevailing hypotheses. Rather, we postulate that Southeast Asia provided a genetic source for two independent migrations, one toward Taiwan and the other toward Polynesia through island Southeast Asia.

Wulf Schiefenhovel - One of the best experts on this subject based on the ideXlab platform.

  • Melanesian origin of Polynesian Y-chromosomes
    Current biology : CB, 2000
    Co-Authors: Manfred Kayser, Silke Brauer, Gunter Weiss, Peter A Underhill, Lutz Roewer, Wulf Schiefenhovel, Mark Stoneking
    Abstract:

    Two competing hypotheses for the origins of Polynesians are the 'express-train' model, which supposes a recent and rapid expansion of Polynesian ancestors from Asia/Taiwan via coastal and island Melanesia, and the 'entangled-bank' model, which supposes a long history of cultural and genetic interactions among Southeast Asians, Melanesians and Polynesians. Most genetic data, especially analyses of mitochondrial DNA (mtDNA) variation, support the express-train model, as does linguistic and archaeological evidence. Here, we used Y-chromosome polymorphisms to investigate the origins of Polynesians. We analysed eight single nucleotide polymorphisms (SNPs) and seven short tandem repeat (STR) loci on the Y chromosome in 28 Cook Islanders from Polynesia and 583 males from 17 Melanesian, Asian and Australian populations. We found that all Polynesians belong to just three Y-chromosome haplotypes, as defined by unique event polymorphisms. The major Y haplotype in Polynesians (82% frequency) was restricted to Melanesia and eastern Indonesia and most probably arose in Melanesia. Coalescence analysis of associated Y-STR haplotypes showed evidence of a population expansion in Polynesians, beginning about 2,200 years ago. The other two Polynesian Y haplotypes were widespread in Asia but were also found in Melanesia. All Polynesian Y chromosomes can be traced back to Melanesia, although some of these Y-chromosome types originated in Asia. Together with other genetic and cultural evidence, we propose a new model of Polynesian origins that we call the 'slow-boat' model: Polynesian ancestors did originate from Asia/Taiwan but did not move rapidly through Melanesia; rather, they interacted with and mixed extensively with Melanesians, leaving behind their genes and incorporating many Melanesian genes before colonising the Pacific.

  • melanesian origin of Polynesian y chromosomes
    Current Biology, 2000
    Co-Authors: Manfred Kayser, Silke Brauer, Gunter Weiss, Peter A Underhill, Lutz Roewer, Wulf Schiefenhovel, Mark Stoneking
    Abstract:

    Results: We analysed eight single nucleotide polymorphisms (SNPs) and seven short tandem repeat (STR) loci on the Y chromosome in 28 Cook Islanders from Polynesia and 583 males from 17 Melanesian, Asian and Australian populations. We found that all Polynesians belong to just three Y-chromosome haplotypes, as defined by unique event polymorphisms. The major Y haplotype in Polynesians (82% frequency) was restricted to Melanesia and eastern Indonesia and most probably arose in Melanesia. Coalescence analysis of associated Y-STR haplotypes showed evidence of a population expansion in Polynesians, beginning about 2,200 years ago. The other two Polynesian Y haplotypes were widespread in Asia but were also found in Melanesia. Conclusions: All Polynesian Y chromosomes can be traced back to Melanesia, although some of these Y-chromosome types originated in Asia. Together with other genetic and cultural evidence, we propose a new model of Polynesian origins that we call the ‘slow-boat’ model: Polynesian ancestors did originate from Asia/Taiwan but did not move rapidly through Melanesia; rather, they interacted with and mixed extensively with Melanesians, leaving behind their genes and incorporating many Melanesian genes before colonising the Pacific.