为了明确肉质相关基因氟烷基因(Hal)、酸肉基因(RN)和脂肪肥胖相关基因(FTO)在国内外不同猪种群体间的遗传变异特性,本研究以大约克、长白、杜洛克和金华猪等猪种群体为研究对象,应用PCR-RFLP技术分别检测了Hal、RN和FTO基因的多态性,并分析了FTO基因上2个多态位点g.276G>T和c.594C>G的遗传变异情况。结果表明:(1)在杜洛克猪中发现了Hal的基因型Hal NHal n,其频率为0.166,但未发现基因型Hal n Hal n,其它猪种群体中仅检测到了基因型Hal NHal N;(2)在已检测的所有猪种群体中只检测到RN基因的rn/rn基因型,未发现rn/RN和RN/RN基因型;(3)在FTO的g.276G>T位点上,金华猪呈现单态,其它猪种群体均呈现多态。在FTO的c.594C>G位点上,4个猪种群体均呈现多态,3个外来猪种群体均以CC基因型频率较高,而金华猪则以GG基因型频率较高。研究结果提示,由于Hal基因在养猪生产中的利弊双重性,因此在某些猪种群体中仍然存在较高频率的Hal NHal n基因型。此外,结合FTO基因的生理功能和已有的研究结果,可在特定的猪群中将其作为影响猪肉质性状的候选基因。本研究发现FTO的基因型分布在我国优良地方猪种金华猪与国外3个种猪群间存在较大差异,为深入研究不同品种猪的肉质形成机理提供了基础数据。
This study investigated the expression profiles of Writ genes in adult porcine Iongissimus dorsi （LD） from different porcine genotypes and their associations with meat quality. The results showed that Wnt5a gene expression level was the highest in Jinhua （JHP） pigs, followed by Zhongbai （ZBP）, DurocxZhongbai （DZB）, and Duroc×Yorkshire×Landrace （DYL） pigs, with significant differences between ZBP, DZB, and DYL （P〈0.05）. This genotypic order was reversed for Wnt7a, Wnt10b, and Wnt11 expression, with JHP and DYL having the lowest and highest expressive levels, respectively. Wnt5a expression was negatively correlated with pH,5 min and ApH （P〈0.01）, some glycolytic markers （P〈0.05）, and positively correlated with meat color （a＊）, shear force （SF） value （P〈0.05）, myosion heavy chain （MyHC） I mRNA proportion （P〈0.01）, turnover ratio of creatine phosphate （CP）, and creatine kinase （CK） activity （P〈0.05）. Opposite correlations were observed for Writ2, Wnt7a, Wnt10b, and Wnt11. These results revealed that Wnt5a, Wnt7a, Wnt10b, and Wnt11 gene expressions in adult porcine muscle contributed to differences between porcine genotypes and affected pork quality. Wnt5a gene expression could be beneficial for the formation of high quality pork by regulating muscle fiber types and postmortem energy metabolism.
