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推断奥姆斯克出血热病毒的进化时间表
Artem N Bondaryuk1,2, Olga I Belykh2, Evgeny I Andaev1
1Laboratory of Natural Focal Viral Infections, Irkutsk Antiplague Research Institute of Siberia and the Far East, Irkutsk 664047, Russia.
Viruses
|July 29, 2023
概括
新的基因组数据显示,奥姆斯克出血性发烧病毒 (OHFV) 的进化速度比以前想象的要快. 这项研究提供了更可靠的OHFV估计.
科学领域:
- 病毒学 病毒学
- 分子进化分子进化
- 人类遗传学 是一个学科.
背景情况:
- 以前的奥姆斯克出血热病毒 (OHFV) 进化研究依赖于有限的完整基因组 (CG) 序列,可能会影响准确性.
- 之前的评估缺乏时间信号评估,这引发了对进化速率和分歧时间估计的可靠性的担忧.
研究的目的:
- 利用47个OHFV CG序列的扩展数据集 (截至2022年7月) 来推断无偏的进化速率和分歧时间.
- 严格评估OHFV基因组数据中的时间信号.
- 为了比较OHFV与其他传播脑炎病毒的进化动态.
主要方法:
- 使用TempEst软件进行回归分析,在完整的开放阅读框架 (ORF) 和E基因数据集中评估时钟式行为.
- 用贝叶斯因子评估时间信号强度的贝叶斯系遗传推断.
- 遗传学分析和过去人口动态的重建.
主要成果:
- 完整的ORF序列表现出比E基因序列 (R2 = 0.11) 更强烈的钟形行为 (R2 = 0.42).
- 贝叶斯分析证实了所有OHFV数据集中的非常强的时间信号.
- 这项研究确定了更精确的OHFV替代率 (9.1 × 10−51.8 × 10−4次/地点/年) 和根高度 (416896年前).
- OHFV的替代率至少比传播脑炎病毒高3.8倍.
- 遗传学分析表明OHFV遗传多样性的下降趋势.
- 有证据表明,在隐性OHFV亚群中,局部进化和指数增长阶段存在.
结论:
- 由于OHFV CG序列的可用性增加,使得进化速率和差异时间的估计更可靠.
- 与传播的脑炎病毒相比,OHFV的进化速度显著更高.
- 尽管多样性下降,但OHFV亚种群显示出当地适应和过去指数增长的证据.
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