观察到的SARS-CoV-2基因组中的突变模式,来自加拿大安大略省主要公共卫生事件所界定的连续时期的样本:基因组监测研究
David Chen1, Gurjit S Randhawa2, Maximillian Pm Soltysiak1
1Department of Biology, Western University, London, ON, Canada.
JMIR bioinformatics and biotechnology
|June 27, 2024
概括
在安大略省的SARS-CoV-2基因组监测显示了与公共卫生事件相关的突变模式的转变. 观察到U>C替代的增加和尖端蛋白的积极选择,突出显示了病毒的进化.
科学领域:
- 病毒学 病毒学
- 基因组学就是基因组学.
- 流行病学 流行病学
背景情况:
- 新出现的SARS-CoV-2变种由于传播能力和毒性增加,造成了公共卫生风险.
- 随着时间的推移,了解基因组突变模式可以阐明驱动变体出现的因素,例如免疫选择和增加的适应性.
- 在安大略省研究SARS-CoV-2的演变,为省特定公共卫生政策的影响提供了洞察力.
研究的目的:
- 综合分析来自加拿大安大略省的SARS-CoV-2序列中的单基替代 (SBS) 类型,数量和基因组位置.
- 为了比较四个不同时代的突变模式,由两年时间内的重大公共卫生事件定义.
- 为了追踪SARS-CoV-2突变格局的进化动态.
主要方法:
- 从GISAID获得的来自安大略省的24,244个SARS-CoV-2基因组序列和元数据 (2020年1月 - 2021年12月) 的分析.
- 序列根据采样日期和相关的公共卫生事件被分为四个时代.
- 与MN996528.1参考基因组相比,确定了单基替代 (SBS),并生成了目录以评估选择和突变集群. 奥格尔管道用于健身估计.
主要成果:
- 观察到的SBS偏差与宿主抗病毒防御机制保持一致.
- 在Epoch 4中,发现了与作用于RNA (ADAR) 活性的腺氨酶相关的U>C替代物的独特增加.
- 新型SBS的最大负担发生在第二个时代 (中位数5) 中,其次是第三个时代 (中位数4).
- 在尖端蛋白ORF1a和ORF3a中确定了突变集群.
- 在第4个时代中,高比例的非同义SBS和dN/dS比超过1表明尖端蛋白的积极选择压力.
结论:
- 在安大略省对SARS-CoV-2突变的定量分析追踪了与公共卫生事件相关的动态,揭示了选择和突变发生的转变.
- 持续的基因组监测对于通报公共卫生政策至关重要,以应对不断发展的COVID-19大流行和新出现的变种.
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