Exploring the Impact of Insertion/Deletion in FTO and PLIN1 Genes on Morphometric Traits in Sheep

SIMPLE SUMMARY: Fat mass and obesity-associated (FTO) and perilipin1 (PLIN1) genes have been associated with fat mass deposition. These genes have also been found to regulate economic traits (e.g., morphometric traits) in animals. In this study, the researchers analyzed insertion–deletion (InDel) variations in the FTO and PLIN1 genes and their association with morphometric traits in three sheep breeds (Hu sheep, Dupor sheep, and Small Tail Han sheep). A total of six InDels (FTO-2, FTO-3, FTO-4, FTO-5, FTO-6, and PLIN1) were identified in the FTO and PLIN1 genes in the three breeds of sheep. Genetic variations of these InDels were evaluated on the basis of their polymorphism information content (PIC). The FTO-6 and PLIN1 genes showed low levels of polymorphism (0 < PIC < 0.25), while the other four InDels were moderately polymorphic (0.25 < PIC < 0.50) in the three breeds of sheep. The results of the association analysis revealed that four InDels from the FTO and PLIN1 genes were significantly associated with the morphometric traits in the three sheep breeds, such as body weight, body height, chest width, chest depth, cannon circumference, head length, coccyx length, forehead width, and back height. Based on these findings, the FTO and PLIN1 genes can serve as genetic markers to select sheep with desirable morphometric traits. ABSTRACT: This study aimed to identify InDels from the FTO and PLIN1 genes and to analyze their association with morphometric traits in Hu sheep (HS), Dupor sheep (DS), and Small Tail Han sheep (STHS). The FTO and PLIN1 genes were genotyped using the insertion/deletion (InDel) method. A one-way ANOVA with SPSS 26.0 software (IBM Corp, Armonk, NY, USA) was used to assess the effect of the InDel FTO and PLIN1 genes on morphometric traits. The results revealed significant associations between certain InDels and the morphometric traits in different breeds of sheep. Specifically, FTO-2 was significantly associated with cannon circumference (CaC) in HS rams and body height (BoH) in HS ewes (p < 0.05). FTO-2 was also significantly associated with chest width (ChW), CaC, head length (HeL), and coccyx length (CoL) in the STHS breed (p < 0.05). FTO-3 showed significant associations with BoH in HS rams and BoH, back height (BaH), ChW, and chest depth (ChD) in HS ewes (p < 0.05). FTO-3 was also significantly associated with ChW in the DS and STHS breeds (p < 0.05). FTO-5 was significantly associated with body weight (BoW) in the DS breed and BoH in the STHS breed (p < 0.05). Furthermore, PLIN1 was significantly related to BoW in the DS breed and was significantly associated with CoL and forehead width (FoW) in the STHS breed (p < 0.05). In conclusion, the study suggested that InDels in the FTO and PLIN1 genes could provide practical information to improve morphometric traits in sheep breeding.