中文摘要：

根据绵羊骨形态发生蛋白受体IB（bone morphogenetic protein receptor IB,BMPR-IB）基因部分调控区的mRNA序列设计3对引物,采用PCR-SSCP技术检测BMPR-IB基因部分3′非翻译区序列在绵羊（Ovis aries）高繁殖力品种（小尾寒羊和湖羊）和低繁殖力品种（特克塞尔和中国美利奴绵羊）中的单核苷酸多态性,同时研究该基因对小尾寒羊和湖羊高繁殖力的影响。结果发现,引物P1扩增片段存在多态性,其余2对引物的扩增片段均不存在多态性。对于引物P1,只在湖羊中发现AA和BB两种基因型,其余3个品种均为AA型;测序表明BB型与AA型相比有2个碱基突变（121T→C和195T→C）;湖羊AA和BB基因型频率分别为0.575和0.425,湖羊AA和BB基因型之间产羔数的最小二乘均值差异不显著（P〉0.05）。研究结果初步表明,检测的BMPR-IB基因位点对小尾寒羊和湖羊高繁殖力都没有显著影响。

英文摘要：

The bone morphogenetic protein receptor IB （BMPR-IB） gene was studied as a candidate gene for the prolificacy of Small Tail Han and Hu sheep （Ovis aries ）. Three pairs of primers were designed to detect single nucleotide polymorphisms of partial 3′ untranslated region （UTR） of BMPR-IB gene in both high fecundity breeds （Small Tail Han and Hu sheep） and low fecundity breeds （ Texel and Chinese Merino sheep） by PCR-SSCP. Only the products amplified by primer PI displayed polymorphisms. For primer PI, two genotypes （AA and BB） were detected in Hu sheep, and only one genotype AA in the other three breeds. Sequencing revealed two mutations （ 121T→C and 195T→C） ofBMPR-IB gene in the genotype BB in comparison to the genotype AA. In Hu sheep, frequency of AA and BB genotypes was 0.575 and 0.425, respectively. The difference of least squares mean for litter size of AA and BB was nonsignificant （P 〉 0.05） in Hu sheep. These results preliminarily show that the detected loci of BMPR-IB gene has no significant effect on high fecundity of Small Tail Han and Hu sheep.