5个绵羊群体MTNR1A基因的多态性与产羔数的关联分析

ASSOCIATION ANALYSIS BETWEEN POLYMORPHISM OF MTNR1A GENE AND LITTER SIZE IN FIVE SHEEP POPULATIONS

为探究绵羊MTNR1A基因在5个绵羊群体之间的多态性与基因功能,本研究以杜泊羊、滩寒羊、杂一代、杂二代、横交一代5个绵羊群体为研究对象,利用飞行质谱检测技术对5个绵羊群体MTNR1A基因g.15118428T>C、g.15118664G>T、g.15119130C>T共3个错义突变位点进行检测,并利用相关生物信息学软件预测分析该基因编码蛋白的理化性质、结构和蛋白互作等。结果表明,MTNR1A基因g.15118428T>C和g.15118664G>T这2个位点在5个群体中均为低度多态(PIC<0.25),g.15119130C>T位点在5个群体中均表现为中度多态(0.25<PIC<0.5)。对3个位点的不同基因型与5个群体的产羔数进行关联分析,结果表明各基因型与产羔数间差异均不显著,说明这3个位点不适用于5个绵羊群体的多羔性状的选育。通过生物信息分析表明,绵羊MTNR1A蛋白理论等电点为9.58,脂肪系数为115.77,总平均亲水性为0.598,为稳定的疏水性碱性蛋白,3个位点突变前后MTNR1A基因编码蛋白二级结构均发生变化,本研究为绵羊繁殖力的标记辅助选择和育种提供一定的理论依据。

In order to explore the polymorphism and gene function of MTNR1 A gene in five sheep populations,five sheep populations of Duper sheep,Tanghan sheep,hybrid generation 1,hybrid 2 generation and cross generation 1 were used to detect the three loci of MTNR1 A gene g.15118428 T>C,g.15118664 G>T and g.15119130 C>T in five sheep populations by flight mass spectrometry.The physicochemical properties,structure and protein interaction of the protein encoded by the gene were predicted and analyzed by using relevant bioinformatics software.The results showed that the loci of g.15118428 T>C and g.15118664 G>T of MTNR1 A gene showed low polymorphism in all five populations(PIC<0.25,0.25,15119130 C>T),and moderate polymorphism of g.15119130 C>T in all five populations(0.25<PIC<0.50).The association analysis between different genotypes of 3 loci and lambing number of 5 populations showed that there was no significant difference between each genotype and lambing number,indicating that these three loci were not suitable for the breeding of multiple lamb traits in 5 sheep populations.Bioinformatics analysis showed that the theoretical isoelectric point of sheep MTNR1 A protein was 9.58,the fat coefficient was 115.77,and the total average hydrophilicity was 0.598,which was a stable hydrophobic basic protein.The secondary structure of mTNR1 A gene coding protein changed before and after mutation of the three sites.This study provides a theoretical basis for marker-assisted selection and breeding of sheep fecundity.