A novel polymorphism of resistin gene and its association with meat quality traits in Chinese Bos taurus
Searching for candidate gene polymorphisms and their relationship with meat quality traits is an important issue for Bos taurus industry. In this study, we evaluated polymorphism of resistin (RETN) gene involved in energy metabolism. Using the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) technology, a novel missense substitution single-nucleotide polymorphism (SNP) g.2528T>C was identified in the exon 2 region of the RETN gene. Allele frequencies, gene heterozygosity, effective allele number and polymorphism information content of the bovine RETN SNP in six populations were investigated and calculated by the χ2 test. The distribution of the polymorphism from the studied six B. taurus breeds was not uniform. Our results suggested that Qinchuan, Luxi and Luxi × Simmental were not in Hardy-Weinberg equilibrium. Moreover, the polymorphism and its association with meat quality traits were analyzed in 369 Qinchuan and 73 Nanyang individuals. The analyzed SNP in the RETN revealed a significant association with marbling and intramuscular fat (p < 0.05). We observed that TT genotype was associated with a heightened marbling score when compared with the TC and CC in Qinchuan and Nanyang breeds. In Qinchuan breed, we also found that TT genotype was associated with an increased intramuscular fat content when compared with the TC. Such associations were not observed on backfat thickness, loin-muscle area and loin-muscle depth. This study showed that polymorphism of the RETN gene is potentially associated with B. taurus meat quality traits.
Key words: Bos taurus, meat quality traits, polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), resistin gene, single nucleotide polymorphism (SNP).