Genetic Architecture of Hock Joint Bumps in Pigs: Insights from ROH and GWAS Analyses

The genetic mechanisms underlying the formation of defects, such as bumps and growths on the hock joints in pigs, remain poorly understood. Therefore, the aim of this study was to investigate the relationship between runs of homozygosity (ROH) and the formation of hock joint bumps, with the goal of identifying associated SNPs and candidate genes involved in these defects. The study was conducted on a population of Large White breed pigs (n = 568) using runs of homozygosity (ROH) analysis and genome-wide association studies (GWAS). The results suggested that the predisposition to hock joint bumps in pigs may have arisen due to recent selective breeding pressure. Using GWAS, 27 SNPs were identified at the suggestive significance level, with one SNP (rs325478346) reaching genome-wide significance. These markers are localized in genes associated with various biological processes, including lipid metabolism (VIPR2 and CFTR), inflammatory processes (MTURN and ADCY2), connective tissue structural integrity (COL27A1), muscle regeneration (PAMR1), and ion exchange and cellular homeostasis (KCNIP4 and NALCN), as well as regulation of cell growth, extracellular matrix remodeling, and fibroblast differentiation (CEP120 and SCUBE3). Further research utilizing omics technologies will provide deeper insights into the pathogenesis of hock joint bumps and contribute to the development of strategies for the prevention and potential treatment of this defect.