MBE Advance Access published online on June 17, 2009
Molecular Biology and Evolution, doi:10.1093/molbev/msp118
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Research Article |
INTEGRATING Y-CHROMOSOME, MITOCHONDRIAL AND AUTOSOMAL DATA TO ANALYSE THE ORIGIN OF PIG BREEDS
1 Departament de Ciència Animal i dels Aliments, Universitat Autònoma de Barcelona, Bellaterra 08193, Spain
2 Key Laboratory for Animal Biotechnology of Jiangxi Province and the Ministry of Agriculture of China, Jiangxi Agricultural University, Nanchang 330045, China
3 Molecular and Medical Genetics Department, King's College London, Saint Thomas St, London, UK
4 International Livestock Research Institute, Nairobi, Kenya, P.O. Box 30709
5 Department of Animal Science, Faculty of Agriculture, Obafemi Awolowo University, Ile-Ife-Nia, Nigeria
6 Department of Animal Science, University of Zimbabwe, MP 67 Mount Pleasant, Harare, Zimbabwe
7 Facultad de Ciencias Agroalimentarias, Universidad de Costa Rica, San Pedro, Costa Rica
8 Facultad de Zootecnia, Universidad Nacional Agraria La Molina, La Molina, Perú
9 Estación Experimental - INIA Las Brujas Ruta 48 Km. 10 - Canelones, Instituto Nacional de Investigaciones Agrarias, Uruguay
10 Animal Genomics & Bioinformatics Division, National Institute of Animal Science, R.D.A., 77 Chuksan-Gil, Kwonsun-Gu, Suwon, 441-706, South Korea
11 Armenian State Agrarian University, 0009 Yerevan, Teryan st. 74, Armenia
12 Institut de Recerca i Estudis Avançats de Catalunya, ICREA, Barcelona, Spain
* Corresponding author: Marcel Amills, Departament de Ciència Animal i dels Aliments, Facultat de Veterinària, Universitat Autònoma de Barcelona, Bellaterra, 08193, Spain. Fax: 34 93 5812106. Telephone number: 34 93 5812876. E-mail: Marcel.Amills{at}uab.es
Received for publication March 23, 2009. Revision received May 27, 2009. Accepted for publication June 1, 2009.
We have investigated the origin of swine breeds through the joint analysis of mitochondrial, microsatellite and Y-chromosome polymorphisms in a sample of pigs and wild boars with a worldwide distribution. Genetic differentiation between pigs and wild boars was remarkably weak, likely as a consequence of a sustained gene flow between both populations. The analysis of nuclear markers evidenced the existence of a close genetic relationship between Near Eastern and European wild boars making difficult to infer their relative contributions to the gene pool of modern European breeds. Moreover, we have shown that European and Far Eastern pig populations have contributed maternal and paternal lineages to the foundation of African and South American breeds. While West African pigs from Nigeria and Benin exclusively harboured European alleles, Far Eastern and European genetic signatures of similar intensity were detected in swine breeds from Eastern Africa. This region seems to have been a major point of entry of livestock species in the African continent as a result of the Indian Ocean trade. Finally, South American creole breeds had essentially a European ancestry although Asian Y-chromosome and mitochondrial haplotypes were found in a few Nicaraguan pigs. The existence of Spanish and Portuguese commercial routes linking Asia with America might have favoured the introduction of Far Eastern breeds into this continent.
Key Words: Domestication • pig • wild boar • phylogeography • Y-chromosome • mitochondrial DNA • microsatellite
Current address: Institute of Evolutionary Biology (UPF-CSIC), Dr. Aiguader 88, 08003 Barcelona, Spain