Department of Microbiology, Faculty of Pharmacy, University of Santiago de Compostela, 5706, Santiago de Compostela, Spain.
Sydney School of Veterinary Science, Faculty of Science, University of Sydney, Sydney, NSW, 2006, Australia.
Arch Microbiol. 2021 Mar;203(2):443-464. doi: 10.1007/s00203-020-02040-5. Epub 2020 Sep 28.
RNA viruses, in general, exhibit high mutation rates; this is mainly due to the low fidelity displayed by the RNA-dependent polymerases required for their replication that lack the proofreading machinery to correct misincorporated nucleotides and produce high mutation rates. This lack of replication fidelity, together with the fact that RNA viruses can undergo spontaneous mutations, results in genetic variants displaying different viral morphogenesis, as well as variation on their surface glycoproteins that affect viral antigenicity. This diverse viral population, routinely containing a variety of mutants, is known as a viral 'quasispecies'. The mutability of their virions allows for fast evolution of RNA viruses that develop antiviral resistance and overcome vaccines much more rapidly than DNA viruses. This also translates into the fact that pathogenic RNA viruses, that cause many diseases and deaths in humans, represent the major viral group involved in zoonotic disease transmission, and are responsible for worldwide pandemics.
RNA 病毒通常表现出很高的突变率；这主要是由于它们复制所需的 RNA 依赖性聚合酶缺乏校对机制来纠正错误掺入的核苷酸，从而产生很高的突变率，导致这种低复制保真度。这种缺乏复制保真度，再加上 RNA 病毒可以自发突变的事实，导致遗传变异显示出不同的病毒形态发生，以及表面糖蛋白的变异，从而影响病毒的抗原性。这种多样化的病毒群体，通常包含多种突变体，被称为病毒“准种”。它们的病毒粒子的可变性使得 RNA 病毒能够快速进化，从而更快地产生抗病毒耐药性并克服疫苗。这也意味着，导致许多人类疾病和死亡的致病性 RNA 病毒是参与人畜共患病传播的主要病毒群，也是全球大流行的罪魁祸首。
