Go to Top Go to Bottom
Asian-Australas J Anim Sci > Accepted Articles
DOI: https://doi.org/10.5713/ajas.19.0034    [Accepted] Published online May 28, 2019.
Evaluation of the genetic structure of indigenous Okinawa Agu pigs using microsatellite markers
Shihei Touma1,*  , Aisaku Arakawa2  , Takuro Oikawa3
1Okinawa Prefectural Livestock and Grassland Research Center, Nakijin, Okinawa 905-0426, Japan
2Institute of Livestock and Grassland Science, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki 305-0901, Japan
3Faculty of Agriculture, University of the Ryukyus, Nishihara, Okinawa 903-0213, Japan
Correspondence:  Shihei Touma, Tel: +81-980-56-5142, Fax: +81-980-56-4803, Email: toumashh@pref.okinawa.lg.jp
Received: 12 January 2019   • Revised: 17 March 2019   • Accepted: 7 May 2019
Agu pigs are indigenous to the Okinawa prefecture, which is the southernmost region of Japan. Agu pigs were exposed to a genetic bottleneck during the 20th century, due to the introduction of European pig breeds. The objective of this study was to elucidate the genetic structure of Agu pigs and to determine their relationships with those of five European breeds, two Chinese breeds and Ryukyu wild boar using microsatellite markers.
A total of 203 DNA samples consist of 8 pig breeds were used in this study. Genotyping was performed using 21 microsatellite markers distributed across 17 chromosomes.
Numbers of effective alleles in Agu pigs were fewer than in European breeds and Ryukyu wild boar. Among domestic pigs, Agu pigs had the lowest heterozygosity (0.423) and highest inbreeding coefficient (FIS = 0.202), indicating a severe loss of heterozygosity in Agu pigs possibly due to inbreeding. Neighbor-joining tree analysis was performed based on Reynolds’ genetic distances, which clustered Agu pigs with Duroc pigs. However, principal component analysis revealed a unique genetic position of the Agu pig, and the second principal component separated Agu pigs from all other breeds. Structure analysis with the optimal assumption of seven groups (K = 7) indicated that Agu pigs form an independent cluster from the other breeds. In addition, high and significant FST values (0.235–0.413) were identified between Agu pigs and the other breeds.
This study revealed a substantial loss of genetic diversity among Agu pigs due to inbreeding. Our data also suggest that Agu pigs have a distinctive genetic structure, although gene flows from European breeds were observed.
Keywords: Agu Pig; Genetic Structure; Genetic Diversity; Indigenous Okinawa Pig; Microsatellite Marker

Editorial Office
Asian-Australasian Association of Animal Production Societies(AAAP)
Room 708 Sammo Sporex, 23, Sillim-ro 59-gil, Gwanak-gu, Seoul 08776, Korea   
TEL : +82-2-888-6558    FAX : +82-2-888-6559   
E-mail : jongkha@hotmail.com               

Copyright © 2019 by Asian-Australasian Journal of Animal Sciences. All rights reserved.

Close layer
prev next