努比亚山羊BMPR-IB基因多态性与其产羔性状的关联分析

Correlation analysis between Nubian goats BMPR-IB gene polymorphism and its lambing traits

【目的】明确努比亚山羊骨形态发生蛋白受体-IB(BMPR-IB)基因多态性与其产羔性状的关联,为山羊育种寻找新的遗传分子标记。【方法】采用DNA池结合PCR产物直接测序技术检测努比亚山羊BMPR-IB基因全部编码区的变异情况,以时间飞行质谱列阵技术对候选SNP位点进行基因分型,并分析BMPR-IB基因多态性与产羔性状(产羔数、初生重和断奶重)的关联性。【结果】努比亚山羊BMPR-IB基因5'UTR第469位存在A→G碱基突变,内含子1第1664位和内含子9第11344位处存在G→A碱基突变。3个SNP位点(5'UTR 469^(th)、Intron1 1664^(th)和Intron9 11344^(th))存在3种基因型(GG型、GA型和AA型),对应的多态信息含量(PIC)分别为0.37、0.11和0.37,其中Intron1 1664^(th)位点的基因频率和基因型频率处于Hardy-Weinberg平衡状态(P>0.05),5'UTR 469^(th)和Intron9 11344^(th)位点则处于Hardy-Weinberg不平衡状态(P<0.05)。关联分析结果表明,努比亚山羊BMPR-IB基因5'UTR第469位碱基由A→G,其GG型母羊比AA型母羊的产羔数和子代平均初生重有所减少,但子代平均断奶重增加;内含子1第1664位碱基由G→A,其GA型母羊比GG型母羊的产羔数和子代平均初生重均有所增加,但子代平均断奶重减轻;内含子9第11344位碱基由G→A,其AA型母羊比GG型母羊产羔数少,但子代平均初生重和平均断奶重均增加。可见,努比亚山羊BMPR-IB基因的3个SNP位点对其产羔性状均无显著影响(P>0.05)。【结论】努比亚山羊BMPR-IB基因存在3个SNP位点(5'UTR 469^(th)、Intron11664^(th)和Intron9 11344^(th)),但对努比亚山羊产羔性状影响不显著,说明BMPR-IB基因对山羊的产羔性状具有一定种属特异性。

【Objective】The correlation between Nubian goat bone morphogenetic protein receptor-IB(BMPR-IB) gene polymorphism and its lambing traits was clarified to search new genetic molecular markers related to goat breeding.【Method】In this study,DNA pool and PCR products sequencing technique were used to detect the variation of whole coding region of Nubian goat BMPR-IB gene. Time flight mass spectrometry was applied to perform the genotype of candidate SNP loci,and analyze the relationship between polymorphism of BMPR-IB gene and goat lambing traits(lamb number, primary weight and weaning weight).【Result】There was a G→A base mutation at the 469^th position of 5'UTR of BMPR-IB gene of Nubian goat,a G→A base mutation at the 1664th position of intron 1 and the 11343^th position of intron 9. The three SNP loci(5'UTR 469^th,Intron1 1664th and Intron9 11344^th)had three genotypes(GG type,GA type and AA type),the polymorphic information content(PIC)respectively were 0.37,0.11 and 0.37. The gene frequency and genotype frequency of Intron1 1664^th were in Hardy-Weinberg equilibrium state(P>0.05),5'UTR 469th and Intron9 11344th were in Hardy-Weinberg imbalance(P<0.05). Correlation analysis showed that the 5'UTR 469th base of the BMPR-IB gene of Nubian goat was A→G,which resulted in a reduction of the lamb number and the average primary weight of the lamb in GG ewes compared with the AA ewes,but increase of the average weaning weight of the offspring. Intron1 1664th base was mutated from G to A,while the lamb number and the average primary weight of the GA ewes were higher than those of the GG ewes,but the average weaning weight of the offspring was reduced. Intron9 11344th base was mutated from G to A. The AA type ewes had fewer lambs than the GG ewes,and their offspring’s average primary weight and average weaning weight increased.The three SNP loci of BMPR-IB gene of Nubian goat had no significant effects on its lambing traits(P>0.05).【Conclusion】There are three SNP loci in the BMPR-IB gene of Nubian goats(5'UTR 469th,Intron1 1664th and Intron9 11344th),but the effect on the lamb traits of Nubian goats is not significant,indicating that the BMPRIB gene has species specificity on lamb traits for goats.