Department of Animal Science, Iowa State University, Ames, IA.
Department of Animal Science, Chungbuk National University, Cheongju, Chungbuk, Korea.
J Anim Sci. 2018 Jun 4;96(6):2074-2085. doi: 10.1093/jas/sky131.
Heat stress is one of the limiting factors negatively affecting pig production, health, and fertility. Characterizing genomic regions responsible for variation in HS tolerance would be useful in identifying important genetic factor(s) regulating physiological responses to HS. In the present study, we performed genome-wide association analyses for respiration rate (RR), rectal temperature (TR), and skin temperature (TS) during HS in 214 crossbred gilts genotyped for 68,549 single nucleotide polymorphisms (SNP) using the Porcine SNP 70K BeadChip. Considering the top 0.1% smoothed phenotypic variances explained by SNP windows, we detected 26, 26, 21, and 14 genes that reside within SNPs explaining the largest proportion of variance (top 25 SNP windows) and associated with change in RR (ΔRR) from thermoneutral (TN) conditions to HS environment, as well as the change in prepubertal TR (ΔTR), change in postpubertal ΔTR, and change in TS (ΔTS), respectively. The region between 28.85 Mb and 29.10 Mb on chromosome 16 explained about 0.05% of the observed variation for ΔRR. The growth hormone receptor (GHR) gene resides in this region and is associated with the HS response. The other important candidate genes associated with ΔRR (PAIP1, NNT, and TEAD4), ΔTR (LIMS2, TTR, and TEAD4), and ΔTS (ERBB4, FKBP1B, NFATC2, and ATP9A) have reported roles in the cellular stress response. The SNP explaining the largest proportion of variance and located within and in the vicinity of genes were related to apoptosis or cellular stress and are potential candidates that underlie the physiological response to HS in pigs.
热应激是影响猪生产、健康和繁殖力的限制因素之一。鉴定与 HS 耐受性变异相关的基因组区域对于鉴定调节对 HS 生理反应的重要遗传因素非常有用。本研究中，我们对 214 头杂交母猪进行了全基因组关联分析，这些母猪在 68549 个单核苷酸多态性（SNP）上进行了基因型分析，使用了 Porcine SNP 70K BeadChip。考虑到 SNP 窗口解释的表型方差的前 0.1%，我们检测到了 26、26、21 和 14 个基因，这些基因位于 SNP 内，解释了最大比例的方差（前 25 个 SNP 窗口），并与 RR（从热中性（TN）条件到 HS 环境的变化）、青春期前 TR（ΔTR）、青春期后 ΔTR 和 TS（ΔTS）的变化相关。第 16 号染色体上 28.85 Mb 到 29.10 Mb 之间的区域解释了 ΔRR 观察到的变异的约 0.05%。生长激素受体（GHR）基因位于该区域，与 HS 反应相关。与 ΔRR（PAIP1、NNT 和 TEAD4）、ΔTR（LIMS2、TTR 和 TEAD4）和 ΔTS（ERBB4、FKBP1B、NFATC2 和 ATP9A）相关的其他重要候选基因也与细胞应激反应有关。解释最大比例变异的 SNP 位于基因内和附近，与细胞凋亡或应激有关，是潜在的候选基因，它们是猪对 HS 生理反应的基础。
