title: Prehistoric introduction of domestic pigs onto the Okinawa Islands: ancient mitochondrial DNA evidence.
abstract: Ancient DNAs of Sus scrofa specimens excavated from archaeological sites on the Okinawa islands were examined to clarify the genetic relationships among prehistoric Sus scrofa, modern wild boars and domestic pigs inhabiting the Ryukyu archipelago, the Japanese islands, and the Asian continent. We extracted remain DNA from 161 bone specimens excavated from 12 archaeological sites on the Okinawa islands and successfully amplified mitochondrial DNA control region fragments from 33 of 161 specimens. Pairwise difference between prehistoric and modern S. scrofa nucleotide sequences showed that haplotypes of the East Asian domestic pig lineage were found from archaeological specimens together with Ryukyu wild boars native to the Ryukyu archipelago. Phylogenetic analysis of 14 ancient sequences (11 haplotypes; 574 bp) indicated that S. scrofa specimens from two Yayoi-Heian sites (Kitahara and Ara shellmiddens) and two Recent Times sites (Wakuta Kiln and Kiyuna sites) are grouped with modern East Asian domestic pigs. Sus scrofa specimens from Shimizu shellmidden (Yayoi-Heian Period) were very closely related to modern Sus scrofa riukiuanus but had a unique nucleotide insertion, indicating that the population is genetically distinct from the lineage of modern Ryukyu wild boars. This genetic evidence suggests that domestic pigs from the Asian continent were introduced to the Okinawa islands in the early Yayoi-Heian period (1700-2000 BP), or earlier.
authors.affiliation: Department of Bioresource Chemistry, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Takuma
authors.initials: T
authors.lastname: Watanobe
authors.forename: Naotaka
authors.initials: N
authors.lastname: Ishiguro
authors.forename: Masuo
authors.initials: M
authors.lastname: Nakano
authors.forename: Hiroto
authors.initials: H
authors.lastname: Takamiya
authors.forename: Akira
authors.initials: A
authors.lastname: Matsui
authors.forename: Hitomi
authors.initials: H
authors.lastname: Hongo
mesh_terms: D000818:Animals; D000829:Animals, Domestic / Q000235:genetics; D001106:Archaeology; D004272:DNA, Mitochondrial; D019143:Evolution, Molecular; D006239:Haplotypes; D007564:Japan; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D034421:Sus scrofa / Q000235:genetics*
chemical_list: D004272:DNA, Mitochondrial