为探索BMPR1A基因在不同生理时期（卵泡期和黄体期）和不同繁殖力（单羔组和多羔组）小尾寒羊组织表达特征及其多样性与小尾寒羊产羔数的关系，采用qPCR技术检测BMPR1A基因在小尾寒羊14种组织中的表达特征。同时，采用Sequenom MassARRAY SNP技术对BMPR1A基因3个SNPs位点在大群中的多态性进行检测，并与小尾寒羊产羔数进行关联。qPCR结果显示，BMPR1A在14种组织中均有表达，其中在大脑、下丘脑和甲状腺组织高表达；BMPR1A在卵泡期和黄体期多羔组下丘脑和卵巢组织表达量均高于单羔组，但未达到显著水平。分型发现BMPR1A基因g.41128335A>T和g.41127600C>T位点在单、多羔绵羊品种间的基因频率和基因型频率达到显著水平。卡方适合性检验结果显示，3个SNPs在大多数绵羊品种中均处于Hardy-Weinberg平衡状态。关联分析结果发现，3个SNPs多态性与小尾寒羊各胎产羔数均无显著相关，但g.41128335A>T和g.41127598A>G位点突变型产羔数基本上均高于野生型。以上结果初步表明，BMPR1A基因表达与小尾寒羊产羔数增加存在一定程度的正相关，但3个SNPs与小尾寒羊各胎产羔数均无显著关联，说明它们可能均不是影响BMPR1A基因功能的关键位点。
To investigate the expression of BMPR1A in various tissues during different physiological periods (follicular and luteal phases) and in ewes of different fecundity (monotocous and polytocous),and to analyze the association of its polymorphism with litter size in Small Tail Han (STH) sheep,qPCR was used to detect the expression of BMPR1A in 14 tissues in STH sheep,meanwhile,Sequenom MassARRAYSNP assay was applied to genotype three single nucleotide polymorphism sites (SNPs) of BMPR1A gene in different sheep breeds,and then the association between the BMPR1A polymorphism and litter size in STH sheep was analyzed. The results showed that the expression of BMPR1A in hypothalamus and ovary of polytocous ewes was higher than that of monotocous ewes,but did not reach a significant level (P>0.05). From genotyping,the genotype and allele frequencies of g.41128335A>T and g.41127600C>T loci of BMPR1A were significantly different (P<0.05) between polytocous and monotocous sheep breeds. The χ2 test indicated that the three SNPs were under Hardy-Weinberg equilibrium (P>0.05) in most of the sheep breeds. Association analysis showed that three loci of BMPR1A gene had no significant association with the litter size of different groups of STH sheep (P>0.05),and the litter size of mutation was higher than that of wild for g.41128335A>T and g.41127598A>G loci. Therefore,we concluded that there may be a certain positive correlation between the expression of BMPR1A gene and litter size in STH sheep,but the three SNPs had no significant association with the litter size of STH sheep,which indicated they may not be the key loci that affect the expression or function of BMPR1A.