Genome-wide association study of heat stress response in Bos taurus

Heat stress is a major challenge in cattle production, affecting animal welfare, productivity, and the economic viability of the industry. In this study, we conducted a genome-wide association study to identify genetic markers associated with heat stress tolerance in Chinese Holstein cattle. We genotyped 68 cows using Illumina 150K Bovine BeadChip microarray and analyzed 112,081 single nucleotide polymorphisms using a linear model-based GWAS approach. We identified 17 SNPs distributed over three chromosomes that showed statistically significant associations with heat stress tolerance in Chinese Holstein cattle. Five of them were located in introns of two genes, PDZRN4 and PRKG1. PDZRN4 is involved in protein degradation pathways, while PRKG1 encodes a protein kinase involved in smooth muscle relaxation and blood vessel dilation. Our findings highlight the potential importance of PDZRN4 and PRKG1 in heat stress tolerance in cattle and provide valuable genetic markers for further research and breeding programs aimed at improving heat stress tolerance in Holstein cattle. However, further studies are needed to elucidate the exact mechanisms by which these SNPs contribute to heat stress tolerance and their potential implications for practical cattle breeding strategies.