RNA viruses are often thought of as possessing almost limitless adaptability as a result of their extreme mutation rates. However, high mutation rates also put a cap on the size of the viral genome by establishing an error threshold, beyond which lethal numbers of deleterious mutations accumulate. Herein, I argue that a lack of genomic space means that RNA viruses will be subject to important evolutionary constraints because specific sequences are required to encode multiple and often conflicting functions. Empirical evidence for these constraints, and how they limit viral adaptability, is now beginning to accumulate. Documenting the constraints to RNA virus evolution has important implications for predicting the emergence of new viruses and for improving therapeutic procedures.

中文翻译：

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错误阈值和 RNA 病毒进化的限制。


RNA 病毒由于其极高的突变率，通常被认为具有几乎无限的适应性。然而，高突变率也通过建立错误阈值限制了病毒基因组的大小，超过该阈值，就会积累致命数量的有害突变。在此，我认为基因组空间的缺乏意味着 RNA 病毒将受到重要的进化限制，因为需要特定的序列来编码多种且经常相互冲突的功能。这些限制以及它们如何限制病毒适应性的经验证据现在已经开始积累。记录 RNA 病毒进化的限制对于预测新病毒的出现和改进治疗程序具有重要意义。