Genetic variation and the fate of beneficial mutations in asexual populations. Author Gregory Lang, David Botstein, Michael Desai Publication Year 2011 Type Journal Article Abstract The fate of a newly arising beneficial mutation depends on many factors, such as the population size and the availability and fitness effects of other mutations that accumulate in the population. It has proved difficult to understand how these factors influence the trajectories of particular mutations, since experiments have primarily focused on characterizing successful clones emerging from a small number of evolving populations. Here, we present the results of a massively parallel experiment designed to measure the full spectrum of possible fates of new beneficial mutations in hundreds of experimental yeast populations, whether these mutations are ultimately successful or not. Using strains in which a particular class of beneficial mutation is detectable by fluorescence, we followed the trajectories of these beneficial mutations across 592 independent populations for 1000 generations. We find that the fitness advantage provided by individual mutations plays a surprisingly small role. Rather, underlying "background" genetic variation is quickly generated in our initially clonal populations and plays a crucial role in determining the fate of each individual beneficial mutation in the evolving population. Keywords Mutation, Models, Genetic, Saccharomyces cerevisiae, Evolution, Molecular, Genetic Variation, Genes, Reporter, Genetics, Population, Selection, Genetic, Flow Cytometry, Microscopy, Fluorescence, Fluorescence, Genetic Fitness, Adaptation, Biological, Population Density, Reproduction, Asexual Journal Genetics Volume 188 Issue 3 Pages 647-61 Date Published 07/2011 Alternate Journal Genetics Google ScholarBibTeXEndNote X3 XML