• Corpus ID: 18406633

Rare beneficial mutations can halt Muller's ratchet

@article{Goyal2011RareBM,
  title={Rare beneficial mutations can halt Muller's ratchet},
  author={Sidhartha Goyal and Daniel J. Balick and Elizabeth R. Jerison and Richard A. Neher and Boris I. Shraiman and Michael M. Desai},
  journal={arXiv: Populations and Evolution},
  year={2011}
}
The vast majority of mutations are deleterious, and are eliminated by purifying selection. Yet in finite asexual populations, purifying selection cannot completely prevent the accumulation of deleterious mutations due to Muller's ratchet: once lost by stochastic drift, the most-fit class of genotypes is lost forever. If deleterious mutations are weakly selected, Muller's ratchet turns into a mutational "meltdown" leading to a rapid degradation of population fitness. Evidently, the long term… 

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