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arXiv · 0901.0663

Robustness and epistasis in mutation-selection models

Andrea Wolff·Joachim Krug
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Abstract

We investigate the fitness advantage associated with the robustness of a phenotype against deleterious mutations using deterministic mutation-selection models of quasispecies type equipped with a mesa shaped fitness landscape. We obtain analytic results for the robustness effect which become exact in the limit of infinite sequence length. Thereby, we are able to clarify a seeming contradiction between recent rigorous work and an earlier heuristic treatment based on a mapping to a Schrödinger equation. We exploit the quantum mechanical analogy to calculate a correction term for finite sequence lengths and verify our analytic results by numerical studies. In addition, we investigate the occurrence of an error threshold for a general class of epistatic landscape and show that diminishing epistasis is a necessary but not sufficient condition for error threshold behavior.

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Andrea Wolff, Joachim Krug. 2009-01-06. Robustness and epistasis in mutation-selection models. https://doi.org/10.1088/1478-3975%2F6%2F3%2F036007

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