貂源冠状病毒与2019新型冠状病毒的遗传进化关系

Analysis on Genetic Evolutionary Relationship between Marten Coronavirus and HCoV-19

为进一步明确貂源冠状病毒与新型人冠状病毒HCoV-19的遗传进化关系,比较了NCBI上公布的3株水貂冠状病毒、5株雪貂冠状病毒以及人冠状病毒HCoV-19和SARS-Cov的全基因组、ORF1a、ORF1ab和病毒表面蛋白Spike的序列同源性,分析了其遗传进化关系,以及组成病毒的结构蛋白和非结构蛋白的种类、基因位置及氨基酸数量。结果显示:貂源冠状病毒与新型冠状病毒HCoV-19全基因组、ORF1a、ORF1ab、Spike蛋白的相似性分别为68%、46.96%、52.44%、47.36%;貂源冠状病毒与HCoV-19不属于同一分支,且亲缘关系较远;同时,貂源冠状病毒与HCoV-19全基因组在蛋白组成、氨基酸数量、基因位置上均存在显著差异。结果表明,貂源冠状病毒与新型冠状病毒HCoV-19不是同一种冠状病毒,此次在人群中流行的新型冠状病毒HCoV-19由貂源冠状病毒重组而成的可能性很小,因此可初步排除HCoV-19来源于水貂和雪貂的可能性。

In order to further clarify the genetic evolutionary relationship between marten coronavirus(MCoV)and 2019 novel coronavirus(HCoV-19),the sequence homology of complete genomes,ORF1 a,ORF1 ab and spike proteins of HCoV-19,SARS-Cov,three strains of mink coronavirus and five strains of ferret coronavirus published on NCBI were compared,then their genetic evolutionary relationships as well as the types,gene positions and amino acid quantities of structural and non-structural proteins of viruses were analyzed. The results showed that the similarities of complete genomes,ORF1 a,ORF1 ab and spike proteins of HCoV-19 and MCoV were 68%,46.96%,52.44% and 47.36%,respectively;the two kinds of viruses belonged to different clusters,which were not closely related. In addition,there were significant differences in protein composition,amino acid quantity and gene location between the whole genomes of MCoV and HCoV-19. Therefore,it was concluded that the two viruses were different with distant genetic relationship,the HCoV-19 that was currently popular among human population was unlikely to be reconstituted by MCoV,which could exclude the possibility that the HCoV-19 might derive from minks and ferrets.