Genotypic Complexity of Fisher’s Geometric Model

@article{Hwang2017GenotypicCO,
  title={Genotypic Complexity of Fisher’s Geometric Model},
  author={Sungmin Hwang and Su-Chan Park and Joachim H A Krug},
  journal={Genetics},
  year={2017},
  volume={206},
  pages={1049 - 1079}
}
In his celebrated model of adaptation, Fisher assumed a smooth phenotype fitness map with one optimum. This assumption is at odds with the rugged..... Fisher’s geometric model was originally introduced to argue that complex adaptations must occur in small steps because of pleiotropic constraints. When supplemented with the assumption of additivity of mutational effects on phenotypic traits, it provides a simple mechanism for the emergence of genotypic epistasis from the nonlinear mapping of… 
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20 Citations
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Methods Citations
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20 Citations

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Citation Type

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A unified framework for computing the exponential growth rate of the expected number of local fitness maxima as a function of L is developed, and two different universality classes of interaction structures that display different asymptotics of this quantity for large k are identified.
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TLDR
Using evolutionary simulations, it is shown that selection tends to create fitness landscapes that are more rugged than the underlying genotype-phenotype landscape, but this increased ruggedness typically does not frustrate adaptive evolution because the local adaptive peaks in the fitness landscape tend to be nearly as tall as the global peak.
The transformability of genotype-phenotype landscapes
TLDR
It is shown that selection for low or intermediate phenotypic values tends to create fitness landscapes that are more rugged than the underlying genotypes, but surprisingly this increased ruggedness typically does not frustrate adaptive evolution, because the local adaptive peaks in the fitness landscape tend to be nearly as tall as the global peak.
The utility of fitness landscapes and big data for predicting evolution
TLDR
The prospect that the authors may be able to predict the outcome of future evolutionary processes has motivated recent investigations of the factors that determine this predictability, but the utility of information on fitness landscapes for evolutionary predictions has so far been limited.
Epistasis and Adaptation on Fitness Landscapes
Epistasis occurs when the effect of a mutation depends on its carrier’s genetic background. Despite increasing evidence that epistasis for fitness is common, its role during evolution is contentious.…
Universality in the Evolution of Molecular Phenotypes
TLDR
This thesis study makes the step towards systems biology by studying for the first time the asexual co-evolution of biophysical phenotypes on a genome-wide level and finds universality in the scaling laws of fitness statistics under large mutational influx.
Inferring the shape of global epistasis
TLDR
To infer the shape of such global epistasis in three proteins, based on published high-throughput mutagenesis data, a maximum-likelihood inference procedure is developed using a flexible family of monotonic nonlinear functions spanned by an I-spline basis.
Coadapted genomes and selection on hybrids: Fisher’s geometric model explains a variety of empirical patterns
TLDR
A simple fitness landscape model is developed, and it naturally interpolates between previous modeling approaches, involving mildly deleterious recessives, or discrete hybrid incompatibilities, and should be readily extendable to other outstanding questions in the study of hybridization.
Physical constraints on epistasis.
TLDR
By providing a generic mechanistic origin for experimentally observed global epistasis, this work suggests that slow collective physical modes can make biological systems evolvable.
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