Genome-Wide Association Study on Chinese Merino Sheep Alopecia

The alopecia of Chinese Merino sheep (ACMS) has a direct impact on the economic value of fine wool. It is generally considered to be caused by both genetic and environmental factors. We aimed to identify single nucleotide polymorphisms (SNPs) and genomic regions that are associated with ACMS in the Chinese Merino sheep population. To identify the genetic risk factors of alopecia in Chinese Merino sheep population, we carried out a genome-wide association study (GWAS). The 60 Chinese Merino sheep alopecia cases and the 190 Chinese Merino sheep controls were from the same livestock farm. DNA was extracted from ear tissue using the saturated phenol-chloroform method. The DNA was genotyped using the Illumina Ovine SNP50 Bead Chip. After quality control, we detected 4,8335 SNPs, which included four SNPs that are significantly associated with the ACMS of sheep. We identified four quantitative trait loci (QTL) regions for ACMS. These QTLs on Ovis aries (OAR) 2 and OAR26. We observe genome-wide significant association with ACMS at four genomic loci: OAR2_130068033.1, OAR2_216769207.1, OAR2_128282778.1 and OAR26_29848682.1. After gene a notation, we found five candidate genes associated with ACMS, including CTL4A and ITGAV. These candidate genes are involved in derma cell differentiation, diet-induced obesity, and nervous system development. The genomic regions identified in this study provided a start-up point for contribute to similar studies and can facilitate the potential utilization of genes involved in etiology of Chinese Merino sheep alopecia in the future.