Almathen Faisal
Department of Public Health, College of Veterinary Medicine, King Faisal University, Al-Hofuf, Saudi Arabia.
Camel Research Center, King Faisal University, Al-Hofuf, Saudi Arabia.
Front Vet Sci. 2024 Sep 18;11:1443748. doi: 10.3389/fvets.2024.1443748. eCollection 2024.
The Awarik camel population in southwestern Saudi Arabia exhibits unique genetic and phenotypic traits compared to other domestic camel populations. This study aims to explore the genomic signatures of positive selection in Awarik camels to understand their evolutionary history and identify genetic adaptations potentially shared with East African camel populations.
Whole genome sequencing data from nine Awarik camels were analyzed using two robust intra-population haplotype-based statistical methods: integrated haplotype score (iHS) and number of segregating sites by length (nSL). These analyses were conducted to identify candidate regions under positive selection within the Awarik camel genome.
These analyses identified 66 and 53 candidate selection regions, encompassing 185 and 123 genes, respectively. The iHS analysis revealed significant selection signals on chromosomes 15 and 16, including a robust overlap on chromosome 15 (10 regions) involving the TRNAI-AAU gene, suggesting its critical role in adaptive processes. Additionally, chromosome 3 exhibited the highest number of candidate regions totaling 10. The nSL analysis highlighted statistically significant regions on chromosomes 2 and 7, as well as a high concentration of candidate regions on chromosome 14, totaling five regions. Notably, large candidate regions were also identified on chromosome 11 (200 kb: 51.750-51.950 kb) and chromosome 9 (325 kb: 45.825-46.150 kb). Functional annotation of these genes revealed involvement in diverse biological processes including olfactory activity, immune regulation, metabolism, insulin secretion, reproductive performance, kidney function, and cellular signaling, with specific genes like BAG5, septin 7, SLC13A1, PCED1B, BMPR1B, ZAR1, JAKMIP2, and NOTCH2 highlighted. These findings contribute to our understanding of the adaptive mechanisms of Awarik camels and have important implications for breeding and conservation strategies. Further research on these genetic adaptations, particularly those affecting immune response, is crucial to mitigate the impacts of climate change on camel populations.
与其他家养骆驼种群相比，沙特阿拉伯西南部的阿瓦里克骆驼种群表现出独特的遗传和表型特征。本研究旨在探索阿瓦里克骆驼正选择的基因组特征，以了解其进化历史，并确定可能与东非骆驼种群共有的遗传适应性。
使用两种基于群体内单倍型的强大统计方法，即整合单倍型分数（iHS）和按长度计算的分离位点数（nSL），对来自9只阿瓦里克骆驼的全基因组测序数据进行分析。进行这些分析是为了确定阿瓦里克骆驼基因组中正选择下的候选区域。
这些分析分别确定了66个和53个候选选择区域，分别包含185个和123个基因。iHS分析揭示了15号和16号染色体上的显著选择信号，包括1号染色体上（10个区域）涉及TRNAI-AAU基因的强烈重叠，表明其在适应性过程中的关键作用。此外，3号染色体上的候选区域数量最多，总计10个。nSL分析突出了2号和7号染色体上具有统计学意义的区域，以及14号染色体上高浓度的候选区域，总计5个区域。值得注意的是，在11号染色体（200 kb：51.750 - 51.950 kb）和9号染色体（325 kb：45.825 - 46.150 kb）上也发现了大片候选区域。对这些基因的功能注释揭示了它们参与多种生物学过程，包括嗅觉活动、免疫调节、代谢、胰岛素分泌、生殖性能、肾功能和细胞信号传导，其中突出的特定基因有BAG5、septin 7、SLC13A1、PCED1B、BMPR1B、ZAR1、JAKMIP2和NOTCH2。这些发现有助于我们理解阿瓦里克骆驼的适应机制，并对育种和保护策略具有重要意义。对这些遗传适应性，特别是那些影响免疫反应的适应性进行进一步研究，对于减轻气候变化对骆驼种群的影响至关重要。
