Association of osteopontin gene with intramuscular fat content and fatty acid composition traits in pigs
Authors:   Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand, Pothakam Nanthana ,   Center of Excellence on Agricultural Biotechnology: (AG-BIO/PERDO-CHE), Bangkok 10900, Thailand,   Graduate School, Chiang Mai University, Chiang Mai 50200, Thailand, Norseeda Worrarak ,   Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand,   Center of Excellence on Agricultural Biotechnology: (AG-BIO/PERDO-CHE), Bangkok 10900, Thailand,   Graduate School, Chiang Mai University, Chiang Mai 50200, Thailand, Liu Guisheng ,   Institute of Animal Science and Veterinary Medicine, Hubei Academy of Agricultural Sciences, Wuhan 430064, China,   Hubei Key Lab for Animal Embryo Engineering and Molecular Breeding, Wuhan 430064, China, Teltathum Tawatchai ,   Mae Hong Son Livestock Research and Breeding Center, Mae Hong Son, 58000 Thailand, Supakankul Pantaporn ,   Division of Animal Science, School of Agriculture and Natural Resources, University of Phayao, Phayao 56000, Thailand, Naraballobh Watcharapong ,   Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand, Khamlor Trisadee ,   Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand, Sringarm Korawan ,   Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand, Mekchay Supamit ,   Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand,   Center of Excellence on Agricultural Biotechnology: (AG-BIO/PERDO-CHE), Bangkok 10900, Thailand,   Innovative Agriculture Research Center, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand
Published: November 2021

Osteopontin (OPN) is a secreted phosphoprotein that is involved in the development of skeletal muscle and fat deposition. The objectives of this study were to identify the polymorphism of the OPN gene and to analyze the association of the OPN gene with intramuscular fat (IMF) content and fatty acid (FA) composition in pigs. Longissimus thoracis (LT) muscle samples taken from the 10-11th rib were collected from a total of 328 Duroc pigs. Genomic DNA samples were extracted from LT muscle tissues using the phenol-chloroform method. IMF content was measured using the ether extraction method and FA composition was measured by gas chromatography. The porcine OPN polymorphisms were identified by DNA sequencing and were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The association analysis of the OPN gene with IMF and FA composition traits was performed using a general linear model (GLM). Two polymorphic sites (OPN g.2442-2471indel and g.3836A>G) were found in the 5´-flanking region and intron 1 of the porcine OPN gene. The OPN g.2442-2471indel polymorphism was found to be significantly associated with IMF content and ω3 FA levels (P<0.05). Moreover, OPN g.3836A>G polymorphism was significantly associated with the linolenic acid levels in the muscles of pigs (P<0.05). The results of this study indicate that the OPN gene is important to IMF content, as well as linolenic and ω3 FA levels in pigs, and could be used as a candidate gene to improve fat deposition and fatty acid composition in the muscles of pigs.