Ovine ELOVL5 and FASN genes polymorphisms and their correlations with sheep tail fat deposition

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.