【摘要】 脂肪细胞定向和分化因子1 (adipocyte determination and differentiation factor 1, ADD1)是一类重要的真核生物转录因子，在调控脂质代谢过程中发挥重要作用，其在绵羊(Ovis aries)尾部脂肪沉积过程中的作用机理尚不明确。本研究以ADD1为候选基因，寻找与绵羊尾部脂肪沉积相关的遗传多态性位点并用于遗传分子标记。选择98只藏羊和264只阿勒泰羊为研究对象，2个品种各30份血液样本，混合后分别构建DNA混池，对ADD1基因所有外显子区域进行扩增，对筛选到的突变位点进行基因分型，利用Haploview 4.2软件进行连锁不平衡分析。结果显示，绵羊ADD1基因第二外显子上存在3个SNP位点，分别是g.73 C>T,g.154 C>T和g.270 C>T，且处于Hardy-Weinberg平衡状态。遗传多态性分析发现，g.154 C>T位点属于中度多态；在g.270 C>T位点上CC和TT基因型在阿勒泰羊和藏羊中差异显著(P<0.05)，且CC型是阿勒泰羊的优势基因型，TT型是藏羊的优势基因型；连锁不平衡分析发现，g.154 C>T和g.270 C>T之间存在强连锁，构成3种单倍型，其中单倍型CC的频率最高，是阿勒泰羊的优势单倍型，藏羊的优势单倍型是TC型。因此，ADD1基因g.270 C>T位点TT基因型可作为绵羊瘦尾选育的重要候选分子标记，为绵羊选育工作提供了参考依据。更多还原

【Abstract】 Adipocyte determination and differentiation factor 1(ADD1) is an important eukaryotic transcription factor that plays an important role in the regulation of lipid metabolism. The mechanism of its action in the process of tail fat deposition in sheep(Ovis aries) remains unclear. In this study, ADD1 gene was selected as a candidate gene to search for genetic polymorphic loci associated with fat deposition in sheep tail and to be used as genetic molecular markers. A total of 98 Tibetan sheep and 264 Altay sheep were selected as research objects, and 30 blood samples from each of the 2 breeds were mixed, and DNA mixing pools were constructed, respectively. All exon regions of ADD1 gene were amplified, and the gene types of the selected mutation sites were analyzed by Haploview 4.2 software. The results showed that there were 3 SNPs on the second exon of sheep ADD1 gene, which were g.73 C>T, g.154 C>T and g.270 C>T, and they were in HardyWeinberg equilibrium. Genetic polymorphism analysis showed that g. 154 C>T locus was moderately polymorphic. At the g. 270 C>T locus, the CC and TT genotypes were significantly different between Altay sheep and Tibetan sheep(P<0.05), and CC genotype was the dominant genotype of Altay sheep and TT genotype was the dominant genotype of Tibetan sheep. Linkage disequilibrium analysis showed that there was a strong linkage between g.154 C>T and g.270 C>T, which constituted 3 haplotypes, among which haplotype CC had the highest frequency and was the dominant haplotype of Altay sheep, while the dominant haplotype of Tibetan sheep was TC. Therefore, TT genotype at the g. 270 C>T locus of ADD1 gene can be used as an important candidate molecular marker for lean tail breeding of sheep, which also provides a reference basis for the breeding work of sheep.更多还原