Genetic drift and mutational hazard in the evolution of salamander genomic gigantism

@article{Mohlhenrich2016GeneticDA,
  title={Genetic drift and mutational hazard in the evolution of salamander genomic gigantism},
  author={Erik R. Mohlhenrich and Rachel Lockridge Mueller},
  journal={Evolution},
  year={2016},
  volume={70}
}
Salamanders have the largest nuclear genomes among tetrapods and, excepting lungfishes, among vertebrates as a whole. Lynch and Conery (2003) have proposed the mutational‐hazard hypothesis to explain variation in genome size and complexity. Under this hypothesis, noncoding DNA imposes a selective cost by increasing the target for degenerative mutations (i.e., the mutational hazard). Expansion of noncoding DNA, and thus genome size, is driven by increased levels of genetic drift and/or decreased… Expand
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