Reducing tail fat deposition can increase the economic value of a carcass and improve feed efficiency. This study aimed to explore ELOVL5 and FASN polymorphisms associated with tail fat deposition and their expression levels of sheep. Association analysis showed that ELOVL5 synonymous mutation g.62534 C > T was associated with tail width, tail fat weight, and relative tail fat weight (P < 0.05). FASN synonymous mutation g.12694 A > G was associated with tail length and width (P < 0.05). Combined effect analyses indicated significant differences between the combined genotypes and tail fat deposition. Quantitative real-time reverse transcription PCR indicated that the ELOVL5 and FASN expression levels were significantly higher in tail fat than in other tissues (P < 0.05). ELOVL5 expression levels in tail-fat tissue of big-tail sheep was significantly higher than that in small-tail sheep (P < 0.01). FASN expression levels were significantly higher in tail-fat tissue of small-tail sheep than in that of big-tail sheep (P < 0.05). During development, ELOVL5 tail fat expression increased significantly from 0 to 6 months old (P < 0.05), and FASN expression at 3 months old was significantly higher than that at 0 (minimum) and 6 months old (P < 0.05). Therefore, ELOVL5 and FASN polymorphisms could represent new candidate molecular markers and targets to reduce tail fat deposition in sheep.

减少尾部脂肪沉积可以增加屠体的经济价值并提高饲料效率。本研究旨在探讨与绵羊尾部脂肪沉积相关的ELOVL5和FASN多态性及其表达水平。关联分析表明，ELOVL5同义突变g.62534 C> T与尾宽、尾脂肪重和相对尾脂肪重相关（P  < 0.05）。FASN同义突变 g.12694 A> G 与尾长和宽度相关（P  < 0.05）。联合效应分析表明联合基因型和尾部脂肪沉积之间存在显着差异。定量实时逆转录 PCR 表明尾脂肪中ELOVL5和FASN的表达水平显着高于其他组织（P  <0.05）。ELOVL5在大尾羊尾脂肪组织中的表达水平显着高于小尾羊（P  <0.01）。FASN在小尾羊尾脂肪组织中的表达水平显着高于大尾羊（P  <0.05）。发育过程中，0～6月龄ELOVL5尾脂肪表达量显着增加（P  <0.05），3月龄FASN表达量显着高于0（最小）和6月龄（P <0.05）。因此，ELOVL5和FASN多态性可以代表新的候选分子标记和目标，以减少绵羊尾部脂肪沉积。