Analysis on the Relationship between an Intronic Polymorphism in <em>Troponin C</em> Gene (TNNC1) with Pork Quality Traits

Abstract

The objective of this study was to investigate the distribution of genotype and analyze the effect of the intronic polymorphism (g.C716G) of TNNC1 gene on meat quality traits of Mong Cai (MC) pig. In total, 118 animals were used for phenotype record and genotyping by PCR-RFLP method. Results showed that the presence of allele G was more than twice as frequent as allele C at the polymorphic site (0.70vs. 0.30) and the frequency of CC genotype was very low (0.07) compared to CG (0.47) and GG (0.46) genotypes. The pH value at 45 min post- mortem was different (p<0.01) among three genotype groups with the lowest found in pigs bearing CC genotype (6.43). Significantly higher compression force value (6.16 kg) found in CC pigs implied that loins from these animals were less tender than those from CG animals. Other parameters of meat quality including drip loss and meat color were not affected by this polymorphism. Moreover, in the analysis of thirty MC pigs, although the relationship between genotypes and muscle fiber type composition was unclear, there was a trend of increasing IIa fiber and decreasing IIb fiber percentage in pigs with GG genotype (p = 0.059 and p = 0.082, respectively). In conclusion, the SNP examined in TNNC1 gene may be of interest in selection for meat tenderness in MC pigs; however as this is not a causative polymorphism, further studies on the association of TNNC1 with meat quality traits regarding to the interaction with other functional genes in surrounding regions are recommended.