Droughtmaster is a tropical breed of beef cattle that can survive in hot climates and easily adapt to torrid environments. These traits are important in livestock breeding. In this study, we genotyped five single-nucleotide polymorphisms (SNPs) of the AHSA2 gene from 190 cattle belonging to three different breeds (Droughtmaster, Angus and Simmental) by using snapshot technology. This work aimed to identify the valuable molecular marker of heat resistance in cattle. Results showed that Droughtmaster exhibited higher expected heterozygosity and polymorphic information content compared with the two other breeds. The AHSA2-1 locus deviated from the Hardy‒Weinberg equilibrium in the Droughtmaster breed (P < 0.05). Two SNPs in Droughtmaster diverged significantly from Angus and Simmental. The SNPs were identified as AHSA2-3 and AHSA2-4, which were closely linked to the three breeds based on pair-wise FST. AHSA2-4 involved a missense mutation. In summary, the GG genotypes in AHSA2-3 and AHSA2-4 may be candidate genotypes associated with heat resistance traits and may serve as valuable genetic markers for breeding of heat-tolerant beef cattle in the future.

中文翻译：

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使用快照技术在三个牛品种中的 AHSA2 基因 SNP

Droughtmaster 是一种热带肉牛品种，可以在炎热的气候中生存，并且很容易适应炎热的环境。这些性状在牲畜育种中很重要。在这项研究中，我们使用快照技术对属于三个不同品种（Droughtmaster、Angus 和 Simmental）的 190 头牛的 AHSA2 基因的五个单核苷酸多态性 (SNP) 进行了基因分型。这项工作旨在确定牛耐热性的有价值的分子标记。结果表明，与其他两个品种相比，Droughtmaster 表现出更高的预期杂合度和多态性信息含量。AHSA2-1 基因座偏离了 Droughtmaster 品种的 Hardy-Weinberg 平衡（P < 0.05）。Droughtmaster 中的两个 SNP 与 Angus 和 Simmental 存在显着差异。SNP 被鉴定为 AHSA2-3 和 AHSA2-4，与基于成对 FST 的三个品种密切相关。AHSA2-4 涉及错义突变。综上所述，AHSA2-3和AHSA2-4中的GG基因型可能是与耐热性状相关的候选基因型，可作为未来耐热肉牛育种的重要遗传标记。