Properties of selected mutations and genotypic landscapes under Fisher's geometric model.

ABSTRACT: The fitness landscape-the mapping between genotypes and fitness-determines properties of the process of adaptation. Several small genotypic fitness landscapes have recently been built by selecting a handful of beneficial mutations and measuring fitness of all combinations of these mutations. Here, we generate several testable predictions for the properties of these small genotypic landscapes under Fisher's geometric model of adaptation. When the ancestral strain is far from the fitness optimum, we analytically compute the fitness effect of selected mutations and their epistatic interactions. Epistasis may be negative or positive on average depending on the distance of the ancestral genotype to the optimum and whether mutations were independently selected, or coselected in an adaptive walk.

SUBMITTER: Blanquart F 

PROVIDER: S-EPMC4326662 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature