Genome-Wide Association Studies Revealed Several Candidate Genes of Meat Productivity in Saryarka Fat-Tailed Coarse-Wool Sheep Breed

Saryarka sheep belong to fat-tailed coarse-wool sheep breed. This breed is distinguished by increased meat productivity while being competitive in young lamb production. Live weight and body indices are relevant data for assessing sheep body constitution, which directly affects the breeding characteristics and meat productivity of animals. This study aimed to find associations with SNPs and nine phenotypic characteristics of the Saryarka fat-tailed coarse-wool sheep breed including live weight and eight body indices (wither height, rump height, bicoastal diameter, body depth, body length, rump width, heart girth, and cannon bone circumference), and find candidate genes related to these characteristics. A total of 100 animals from the Karaganda region of Kazakhstan were used in this study. Live weight and eight body indices of sheep were measured using tape and electronic scales. The blood samples of the animals were used for DNA extraction. DNA samples were genotyped with the OvineSNP50 Genotyping BeadChip and analyzed using GWAS. Statistically significant SNPs were identified for each characteristic trait referencing the genome of (Oar_v3.1) using BioMart. The GWAS results demonstrated a substantial chromosomal-level correlation between 32 chromosome-wide significant and suggestively significant SNPs in the studied sheep breed. Overall, seven SNPs located in seven different genes were revealed as candidates for live weight and four body indices: s20793.1 SNP in the gene for live weight, OAR4_54217431.1 SNP in the gene for bicoastal diameter, s25229.1 in the gene, and s01175.1 SNP in the gene for rump width, OAR2_175574781.1 SNP in the gene for heart girth, and OAR1_209022621.1 SNP in the gene and s15415.1 SNP in the gene for cannon bone circumference. Some of these genes were previously reported to be involved in body constitution and fat deposit in other sheep breeds. The results of the present study open up new opportunities for targeted sheep breeding for meat and fat productivity.