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DNA mismatch repair: molecular mechanisms and biological function

Mark J Schofield1, Peggy Hsieh

  • 1Genetics and Biochemistry Branch, National Institute of Diabetes, and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA. schofiel@helix.nih.gov

Annual Review of Microbiology
|October 7, 2003
PubMed

Insights

DNA mismatch repair (MMR) maintains genome stability by correcting errors during DNA replication and damage. MMR deficiency leads to elevated mutation rates and is linked to hereditary nonpolyposis colorectal cancer.

Area of Science:

  • Genetics
  • Molecular Biology
  • Genomic Stability

Background:

  • DNA mismatch repair (MMR) is crucial for maintaining genome integrity in all cells.
  • MMR significantly enhances DNA replication fidelity and corrects various DNA errors.
  • Defects in MMR are associated with a mutator phenotype, microsatellite instability, and hereditary cancers.

Purpose of the Study:

  • To summarize the critical roles of DNA mismatch repair in genome maintenance.
  • To highlight the connection between MMR deficiency and increased cancer risk.
  • To underscore MMR's function beyond replication error correction.

Main Methods:

  • Literature review and synthesis of existing research on DNA mismatch repair.
  • Analysis of the molecular mechanisms underlying MMR.
  • Examination of the clinical implications of MMR defects.

Main Results:

  • MMR corrects mispaired bases arising from replication errors, recombination, and DNA damage.
  • Cells lacking functional MMR exhibit a mutator phenotype with high spontaneous mutation rates.
  • MMR deficiency is a key factor in hereditary nonpolyposis colorectal cancer.

Conclusions:

  • DNA mismatch repair is essential for preventing mutations and maintaining genomic stability.
  • MMR functions in post-replication repair, policing homologous recombination, and preventing interspecies genetic exchange.
  • Understanding MMR is vital for cancer prevention and treatment strategies.

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