猪钙蛋白酶抑制蛋白基因PCR-RFLP多态性与肉质性状及背膘厚间的关系分析

钙蛋白酶抑制蛋白(CAST)是钙蛋白酶系统的内源性抑制剂，并且已经被确定能影响宰后肉的嫩度。本研究采用PCR-RFLP技术，分析了CAST基因在125头PIC杂交猪中的多态性分布及其与肉质性状和背膘厚间的相关。结果发现，CAST基因在本研究所检测的位点均具有多态性。进一步分析表明，CAST^A2A2基因型个体与其相应的另外两个基因型个体相比肌内脂肪含量有显著差异，CAST^B1B2基因型个体对于肌内脂肪含量的影响也有相同的趋势；CAST^C1C2基因型个体与其相应的另外两个基因型个体相比背膘厚有显著差异，CAST^C1C2。基因型个体和CAST^D1D2基因型个体对于背膘厚的影响也有相同的趋势。因此可以把CAST基因作为影响猪肉盾性状和屠体性状的候选基因。

Polymorphism Analysis of Porcine Calpastatin Gene by PCR-RFLP and its Associations with Pork Qualities and Thickness of Back Fat

Calpastatin (CAST) is the endogenous inhibitor of the calpain system, which has been found to affect the postmortem tenderization of skeletal muscle. The aim of the study was to characterize the polymorphism of CAST gene with three restriction enzymes(HinfI, MspI, TaqI) in PIC pig and to evaluate the relationship between the CAST genotypes and pork quality traits. The analyses covered a total of 125 fatteners of PIC pig. The pigs appeared to be three genotypes at all loci considered. The association between genotypes at locus of CAST gene and pork quality traits was analyzed on 125 fatteners. The results showed: genotypes A2A2 at locus CAST/HinfI and B1B2 at locus CAST/ MspI were proved more intramuscular fat than two remaining genotypes at each of these loci. Moreover, all of genotypes B1B2 at locus CAST/MspI, C1C2 at locus CAST/HinfI and D1D2 at locus CAST/TaqI have advantage over their respective remaining genotypes for backfat. It was concluded that CAST gene can be used as a candidate gene for pork quality and carcass quality traits.