Weak Selection and Protein Evolution

摘要: The “nearly neutral” theory of molecular evolution proposes that many features genomes arise from the interaction three weak evolutionary forces: mutation, genetic drift, and natural selection acting at its limit efficacy. Such forces generally have little impact on allele frequencies within populations generation to but can substantial effects long-term evolution. dynamics weakly selected mutations are highly sensitive population size, near neutrality was initially proposed as an adjustment neutral account for general patterns in available protein DNA variation data. Here, we review motivation nearly theory, discuss structure model predictions, evaluate current empirical support interactions among Near may be a prevalent mode across range functional categories taxa. However, multiple mechanisms (including adaptive evolution, linked selection, changes fitness-effect distributions, selection) often explain same genome variation. Strong parameter sensitivity remains limitation model, concave fitness functions plausible underlying basis selection.