Synonymous mutations drive adaptive evolution through gene expression and protein folding.
Synonymous mutations, which were thought to be insignificant, can actually impact fitness and drive adaptive evolution by affecting gene expression and protein folding. Microbial experiments have shown that these mutations can have similar fitness effects to non-synonymous mutations, especially beneficial ones. They can influence fitness by creating new RNA binding sites and changing mRNA folding stability. However, clonal interference in evolving populations may limit the role of synonymous mutations in adaptive evolution. Incorrectly assuming these mutations are neutral can hinder our understanding of evolution. Future research should explore the significance of synonymous mutations in driving adaptation.