DDT resistance, epistasis and male fitness in flies

J Evol Biol. 2011 Jun;24(6):1351-62. doi: 10.1111/j.1420-9101.2011.02271.x. Epub 2011 Apr 20.


In Drosophila melanogaster, the DDT resistance allele (DDT-R) is beneficial in the presence of DDT. Interestingly, DDT-R also elevates female fitness in the absence of DDT and existed in populations before DDT use. However, DDT-R did not spread regardless of DDT-independent selective advantages in females. We ask whether sexual antagonism could explain why DDT-R did not spread before pesticide use. We tested pre- and post-copulatory male fitness correlates in two genetic backgrounds into which we backcrossed the DDT-R allele. We found costs to DDT-R that depended on the genetic background in which DDT-R was found and documented strong epistasis between genetic background and DDT-R that influenced male size. Although it remains unclear whether DDT-R is generally sexually antagonistic, or whether the fitness costs noted would be sufficient to retard the spread of DDT-R in the absence of DDT, general fitness advantages to DDT-R in the absence of DDT may be unlikely.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Animals
  • Body Size / genetics
  • DDT*
  • Drosophila melanogaster / anatomy & histology
  • Drosophila melanogaster / drug effects
  • Drosophila melanogaster / genetics*
  • Epistasis, Genetic*
  • Female
  • Insecticide Resistance / genetics*
  • Insecticides*
  • Male
  • Mating Preference, Animal*
  • Spermatozoa / physiology


  • Insecticides
  • DDT