Genome size is negatively correlated with effective population size in ray-finned fish

Trends Genet. 2005 Dec;21(12):643-6. doi: 10.1016/j.tig.2005.09.003. Epub 2005 Oct 5.


A recent theory suggesting that genome size and complexity can increase as a passive consequence of small effective population size has generated much controversy. In this article, we demonstrate that freshwater fish species, which have smaller effective population sizes than marine fish species, have larger genomes. We show that genome size is negatively correlated with genetic variability, independent of phylogeny, body size and generation time. Genome duplication is also observed predominantly in freshwater fish. These results suggest that the raw materials of complexity originate under conditions of reduced selection efficiency.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Fishes / genetics*
  • Fresh Water
  • Genetic Variation
  • Genome*
  • Heterozygote
  • Oceans and Seas
  • Phylogeny
  • Population / genetics