绵羊PTGR1和PTGIS多态性及其与小尾寒羊产羔数的关联分析

Polymorphisms of PTGR1 and PTGIS genes in Sheep and Their Association with Litter Size in Small Tail Han Sheep

文章旨在探究不同绵羊品种PTGR1基因g.11877208A>C位点、PTGIS基因g.77175697C>T位点和g.77175798G>A位点多态分布差异及这3个位点与小尾寒羊产羔数之间的关系,为鉴定绵羊高繁殖力相关的分子标记提供助力。根据全基因组重测序结果,利用Sequenom MassARRAY ■SNP技术对多羔绵羊品种(小尾寒羊、湖羊、策勒黑羊)和单羔绵羊品种(滩羊、苏尼特羊、萨福克羊、草原型藏羊)PTGR1基因1个位点和PTGIS基因2个位点进行分型,并计算这些位点与小尾寒羊产羔数的关联。结果表明,PTGR1基因g.11877208A>C位点和PTGIS基因g.77175798G>A位点在单、多羔绵羊品种中均鉴定出3种基因型,PTGIS基因g.77175697C>T位点在单、多羔绵羊品种中只有CC和CT两种基因型。PTGIS基因g.77175798G>A位点基因型频率和等位基因频率在单、多羔绵羊品种之间均存在极显著差异(P<0.01)。PTGR1基因g.11877208A>C位点在策勒黑羊和滩羊中为低度多态(PIC<0.25),在其他品种中均表现为中度多态(0.25<PIC<0.5);在所有品种中,该位点均不服从哈代-温伯格平衡(P<0.05)。PTGIS基因g.77175697C>T位点,所有品种均表现为低度多态(PIC<0.25),在所检测群体中只有小尾寒羊在该位点服从哈代-温伯格平衡(P>0.05)。在策勒黑羊和萨福克羊中,PTGIS基因g.77175798G>A位点为中度多态(0.25<PIC<0.5),在其他品种中该位点均为低度多态(PIC<0.25);在所检测群体中只有萨福克羊服从哈代-温伯格平衡(P>0.05)。这3个位点与小尾寒羊产羔数关联分析结果表明,PTGR1和PTGIS基因3个SNPs位点多态性与小尾寒羊不同胎次产羔数之间无显著关联(P>0.05)。综上所述,绵羊PTGR1基因g.11877208A>C、PTGIS基因g.77175697C>T和g.77175798G>A位点在小尾寒羊多态分布与其产羔数均无显著关联,这3个位点不适合作为小尾寒羊育种中多羔性状选择的分子标记。

The aim of study was to investigate the polymorphic of g.11877208A>C of prostaglandin reductase 1(PTGR1)gene,g.77175697C>T and g.77175798G>A of prostaglandin I2 synthase(PTGIS)genes in different sheep breeds and the association between three loci and litter size in Small Tail Han sheep,which was to identify molecular markers related to sheep fecundity.Based on the whole genome resequencing results,one locus of PTGR1 gene and two loci of PTGIS gene were genotyped in fecundity sheep breeds(Small Tail Han sheep,Hu sheep,Cele Black sheep)and single-lambing sheep breeds(Tan sheep,Sunit sheep,Suffolk sheep,Tibetan sheep)using Sequenom MassARRAY■ SNP technology.The association of these loci with litter size of Small Tail Han sheep was analyzed.The results showed that there were 3 genotypes of g.11877208A>C of PTGR1 gene and g.77175798G>A of PTGIS gene in monotocous and polytocous sheep breeds.In g.77175697C>T of PTGIS gene was the only CC and CT genotype in monotocous and polytocous sheep breeds.The genotype frequency and allele frequency of g.77175798G>A of PTGIS gene were highly different between monotocous and polytocous sheep breeds(P<0.01).The genetic diversity of g.11877208A>C of PTGR1 gene was low in Cele Black sheep and Hu sheep(PIC<0.25),and moderate(0.25<PIC<0.5)in all other breeds.The locus was not in Hardy-Weinberg equilibrium(HWE)in all breeds(P<0.05).g.77175697C>T of PTGIS gene showed low polymorphism(PIC<0.25)in all breeds,and Small Tail Han sheep was in HWE at this locus(P>0.05).g.77175798G>A of PTGIS gene had moderate genetic diversity(0.25<PIC<0.5)in Cele Black sheep and Suffolk sheep,and low genetic diversity(PIC<0.25)in all other breeds.Only Suffolk sheep was in HWE in the all population(P>0.05).The association analysis results revealed that 3 SNPs of PTGR1 and PTGIS genes were no significantly related with litter size of Small Tail Han sheep(P>0.05).In conclusion,the distribution of g.11877208A>C of PTGR1 gene and g.77175697C>T and g.77175798G>A of PTGIS gene were not significantly associated with litter size of Small Tail Han sheep,and these three loci could not be used for fecundity trait selection in the breeding of Small Tail Han sheep.