DNA mismatch repair: molecular mechanisms and biological function

Annu Rev Microbiol. 2003;57:579-608. doi: 10.1146/annurev.micro.57.030502.090847.


DNA mismatch repair (MMR) guards the integrity of the genome in virtually all cells. It contributes about 1000-fold to the overall fidelity of replication and targets mispaired bases that arise through replication errors, during homologous recombination, and as a result of DNA damage. Cells deficient in MMR have a mutator phenotype in which the rate of spontaneous mutation is greatly elevated, and they frequently exhibit microsatellite instability at mono- and dinucleotide repeats. The importance of MMR in mutation avoidance is highlighted by the finding that defects in MMR predispose individuals to hereditary nonpolyposis colorectal cancer. In addition to its role in postreplication repair, the MMR machinery serves to police homologous recombination events and acts as a barrier to genetic exchange between species.

Publication types

  • Review

MeSH terms

  • Adenosine Triphosphatases / metabolism
  • Bacteria / genetics*
  • Bacteria / metabolism*
  • Bacterial Proteins / metabolism
  • Base Pair Mismatch / physiology
  • DNA Damage / physiology*
  • DNA Repair / physiology*
  • DNA Replication / physiology
  • DNA, Bacterial / metabolism*
  • DNA-Binding Proteins / metabolism
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Escherichia coli Proteins / metabolism
  • Meiosis / physiology
  • Models, Molecular
  • MutL Proteins
  • MutS DNA Mismatch-Binding Protein
  • Recombination, Genetic / physiology


  • Bacterial Proteins
  • DNA, Bacterial
  • DNA-Binding Proteins
  • Escherichia coli Proteins
  • MutL protein, E coli
  • Adenosine Triphosphatases
  • MutL Proteins
  • MutS DNA Mismatch-Binding Protein
  • MutS protein, E coli