Jia Jianlei, Chen Qian, Gui Linsheng, Jin Jipeng, Li Yongyuan, Ru Qiaohong, Hou Shengzhen
Key of laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining, Qinghai 810016, China.
Department of Animal Science, College of agriculture and Animal Husbandry, Qinghai University, Xining, Qinghai 810016, China.
Asian-Australas J Anim Sci. 2019 Jul;32(7):949-955. doi: 10.5713/ajas.18.0541. Epub 2019 Feb 9.
The present study was to investigate the association of polymorphisms in exon-9 of the bone morphogenetic protein receptor-1B (BMPR-1B) gene (C864T) with litter size in 240 Dorset, 232 Mongolian, and 124 Small Tail Han ewes.
Blood samples were collected from 596 ewes and genomic DNA was extracted using the phenol: chloroform extraction method. The 304-bp amplified polymerase chain reaction product was analyzed for polymorphism by single-strand conformation polymorphism method. The genotypic frequency and allele frequency of BMPR-1B gene exon-9 were computed after sequence alignment. The χ2 independence test was used to analyze the association of genotypic frequency and litter size traits with in each ewe breed, where the phenotype was directly treated as category.
The results indicated two different banding patterns AA and AB for this fragment, with the most frequent genotype and allele of AA and A. Calculated Chi-square test for BMPR-1B gene exon-9 was found to be more than that of p value at the 5% level of significance, indicating that the population under study was in Hardy-Weinberg equilibrium for all ewes. The χ2 independence test analyses indicated litter size differences between genotypes was not the same for each breed. The 304-bp nucleotide sequence was subjected to BLAST analysis, and the C864T mutation significantly affected litter size in singletons, twins and multiples. The heterozygosity in exon-9 of BMPR-1B gene could increase litter size for all the studied ewes.
Consequently, it appears that the polymorphism BMPR-1B gene exon-9 detected in this study may have potential use in marker assisted selection for litter size in Dorset, Mongolian, and Small Tail Han ewes.
本研究旨在调查骨形态发生蛋白受体1B（BMPR - 1B）基因外显子9（C864T）中的多态性与240只多塞特母羊、232只蒙古母羊和124只小尾寒羊产羔数之间的关联。
采集596只母羊的血样，采用酚：氯仿提取法提取基因组DNA。通过单链构象多态性方法分析304 bp扩增的聚合酶链反应产物的多态性。序列比对后计算BMPR - 1B基因外显子9的基因型频率和等位基因频率。采用χ2独立性检验分析每个母羊品种中基因型频率与产羔数性状的关联，将表型直接视为类别。
结果表明该片段存在两种不同的条带模式AA和AB，最常见的基因型和等位基因为AA和A。计算得出BMPR - 1B基因外显子9的卡方检验值在5%显著水平下大于p值，表明所研究的群体在所有母羊中处于哈迪 - 温伯格平衡。χ2独立性检验分析表明，各品种不同基因型之间的产羔数差异不同。对304 bp核苷酸序列进行BLAST分析，C864T突变显著影响单羔、双羔和多羔的产羔数。BMPR - 1B基因外显子9的杂合性可增加所有研究母羊的产羔数。
因此，本研究中检测到的BMPR - 1B基因外显子9多态性可能在多塞特、蒙古和小尾寒羊产羔数的标记辅助选择中具有潜在用途。
