Zhang X W, Yap Y L, Danchin A
HKU-Pasteur Research Centre, Hong Kong, P.R. China.
Arch Virol. 2005 Jan;150(1):1-20. doi: 10.1007/s00705-004-0413-9. Epub 2004 Oct 11.
The origin of severe acute respiratory syndrome-associated corona-virus (SARS-CoV) is still a matter of speculation, although more than one year has passed since the onset of the SARS outbreak. In this study, we implemented a 3-step strategy to test the intriguing hypothesis that SARS-CoV might have been derived from a recombinant virus. First, we blasted the whole SARS-CoV genome against a virus database to search viruses of interest. Second, we employed 7 recombination detection techniques well documented in successfully detecting recombination events to explore the presence of recombination in SARS-CoV genome. Finally, we conducted phylogenetic analyses to further explore whether recombination has indeed occurred in the course of coronaviruses history predating the emergence of SARS-CoV. Surprisingly, we found that 7 putative recombination regions, located in Replicase 1ab and Spike protein, exist between SARS-CoV and other 6 coronaviruses: porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), bovine coronavirus (BCoV), human coronavirus 229E (HCoV), murine hepatitis virus (MHV), and avian infectious bronchitis virus (IBV). Thus, our analyses substantiate the presence of recombination events in history that led to the SARS-CoV genome. Like the other coronaviruses used in the analysis, SARS-CoV is also a mosaic structure.
尽管严重急性呼吸综合征相关冠状病毒（SARS-CoV）爆发已过去一年多，但它的起源仍然是一个猜测的问题。在本研究中，我们实施了一个三步策略来检验一个有趣的假设，即SARS-CoV可能源自一种重组病毒。首先，我们将整个SARS-CoV基因组与病毒数据库进行比对，以搜索感兴趣的病毒。其次，我们采用了7种在成功检测重组事件方面有充分记录的重组检测技术，来探索SARS-CoV基因组中重组的存在。最后，我们进行了系统发育分析，以进一步探究在SARS-CoV出现之前的冠状病毒历史进程中是否确实发生了重组。令人惊讶的是，我们发现SARS-CoV与其他6种冠状病毒：猪流行性腹泻病毒（PEDV）、传染性胃肠炎病毒（TGEV）、牛冠状病毒（BCoV）、人冠状病毒229E（HCoV）、鼠肝炎病毒（MHV）和禽传染性支气管炎病毒（IBV）之间，在复制酶1ab和刺突蛋白中存在7个假定的重组区域。因此，我们的分析证实了历史上导致SARS-CoV基因组的重组事件的存在。与分析中使用的其他冠状病毒一样，SARS-CoV也是一种嵌合结构。
