A1 Refereed original research article in a scientific journal
Genetic characterization of populations in the Marquesas Archipelago in the context of the Austronesian expansion
Authors: Tätte Kai, Metspalu Ene, Post Helen, Palencia-Madrid Leire, Luis Javier Rodríguez, Reidla Maere, Tamm Erika, Ilumäe Anne-Mai, de Pancorbo Marian M., Garcia-Bertrand Ralph, Metspalu Mait, Herrera Rene J.
Publisher: NATURE PORTFOLIO
Publication year: 2022
Journal: Scientific Reports
Journal name in source: SCIENTIFIC REPORTS
Journal acronym: SCI REP-UK
Article number: 5312
Volume: 12
Issue: 1
Number of pages: 17
ISSN: 2045-2322
DOI: https://doi.org/10.1038/s41598-022-08910-w
Web address : https://www.nature.com/articles/s41598-022-08910-w
Self-archived copy’s web address: https://research.utu.fi/converis/portal/detail/Publication/175107012
Our exploration of the genetic constitution of Nuku Hiva (n = 51), Hiva Oa (n = 28) and Tahuata (n = 8) of the Marquesas Archipelago based on the analyses of genome-wide autosomal markers as well as high-resolution genotyping of paternal and maternal lineages provides us with information on the origins and settlement of these islands at the fringe of the Austronesian expansion. One widespread theme that emerges from this study is the genetic uniformity and relative isolation exhibited by the Marquesas and Society populations. This genetic homogeneity within East Polynesia groups is reflected in their limited average heterozygosity, uniformity of constituents in the Structure analyses, reiteration of complete mtDNA sequences, marked separation from Asian and other Oceanic populations in the PC analyses, limited differentiation in the PCAs and large number of IBD segments in common. Both the f3 and the Outgroup f3 results provide indications of intra-East Polynesian gene flow that may have promoted the observed intra-East Polynesia genetic homogeneity while ALDER analyses indicate that East Polynesia experienced two gene flow episodes, one relatively recent from Europe that coincides roughly with the European incursion into the region and an early one that may represent the original settlement of the islands by Austronesians. Median Network analysis based on high-resolution Y-STR loci under C2a-M208 generates a star-like topology with East Polynesian groups (especially from the Society Archipelago) in central stem positions and individuals from the different populations radiating out one mutational step away while several Samoan and outlier individuals occupy peripheral positions. This arrangement of populations is congruent with dispersals of C2a-M208 Y chromosomes from East Polynesia as a migration hub signaling dispersals in various directions. The equivalent ages of the C2a-M208 lineage of the populations in the Network corroborate an east to west flow of the most abundant Polynesian Y chromosome.
Downloadable publication This is an electronic reprint of the original article. |  |
