2010/05/17 by Rafael Sanjuán · 1 citation
Biochemistry, Genetics and Molecular Biology · Agricultural and Biological Sciences · #Evolution and Genetic Dynamics #Plant Virus Research Studies #CRISPR and Genetic Engineering
paper · doi:10.1098/rstb.2010.0063
openalex publication_date 2010/05/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/15
The fitness effects of mutations are central to evolution, yet have begun to be characterized in detail only recently. Site-directed mutagenesis is a powerful tool for achieving this goal, which is particularly suited for viruses because of their small genomes. Here, I discuss the evolutionary relevance of mutational fitness effects and critically review previous site-directed mutagenesis studies. The effects of single-nucleotide substitutions are standardized and compared for five RNA or single-stranded DNA viruses infecting bacteria, plants or animals. All viruses examined show very low tolerance to mutation when compared with cellular organisms. Moreover, for non-lethal mutations, the mean fitness reduction caused by single mutations is remarkably constant (0.10-0.13), whereas the fraction of lethals varies only modestly (0.20-0.41). Other summary statistics are provided. These generalizations about the distribution of mutational fitness effects can help us to better understand the evolution of RNA and single-stranded DNA viruses.