Association of porcine UCP3 gene polymorphisms with fatness traits in a PietrainJinhua F2 population

Uncoupling protein 3 (UCP3) is a mitochondrial transmembrane carrier which uncouples oxidative phosphorylation and plays an important role in energy homeostasis and fatty acid transporting. In this study, two missense mutations (T221C and A448G) were detected in porcine UCP3 gene. Genotype frequencies were analyzed using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) in eight pig breeds (n = 384). The results revealed that Chinese native breeds had fixed genotype CC at T221C polymorphic loci. Allele G at the A448G loci has higher frequency than allele A in all pure breeds, except for Pietrain. Association analysis between variants and fatness traits was carried out in a Pietrain×Jinhua F2 population (n = 274). The results showed that two single nucleotide polymorphism (SNPs) were significantly associated with intramuscular fat content (p = 0.023 and p = 0.000, respectively). These results indicated that single nucleotide polymorphism of UCP3 gene is potentially associated with fatness traits in pig. Key words : Pig, uncoupling protein 3 (UCP3), polymorphism, fatness traits, association analysis.