2006/07/20 by Arlin Stoltzfus · 3 citations
Biochemistry, Genetics and Molecular Biology · Neuroscience · #Adaptation (eye) #Biology #Computational biology #Evolution and Genetic Dynamics #Evolutionary biology #Gene #Gene Regulatory Network Analysis #Genetics #Mutation #Neuroscience #RNA Research and Splicing
paper · doi:10.1093/molbev/msl064
openalex publication_date 2006/07/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Evolutionary trends responsible for systematic differences in genome and proteome composition have been attributed to GC:AT mutation bias in the context of neutral evolution or to selection acting on genome composition. A possibility that has been ignored, presumably because it is part of neither the Modern Synthesis nor the Neutral Theory, is that mutation may impose a directional bias on adaptation. This possibility is explored here with simulations of the effect of a GC:AT bias on amino acid composition during adaptive walks on an abstract protein fitness landscape called an "NK" model. The results indicate that adaptation does not preclude mutation-biased evolution. In the complete absence of neutral evolution, a modest GC:AT bias of realistic magnitude can displace the trajectory of adaptation in a mutationally favored direction, to such a degree that amino acid composition is biased substantially and persistently. Thus, mutational explanations for evolved patterns need not presuppose neutral evolution.