mismatch repair

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mis·match re·pair

replacement of mismatched base pairs by removal of the incorrect base and replacement with the correct base by DNA polymerase.

mismatch repair

An intrinsic intracellular mechanism which corrects nucleotide insertion errors made during DNA replication, by excising the mismatched base pairs that escaped correction by the proofreading activities of DNA polymerases and replacing the mismatched bases with the correct ones.

mismatch repair

a DNA REPAIR mechanism that operates to correct errors caused by MISMATCH OF BASES in newly replicated DNA. The newly synthesized DNA strand containing the incorrect BASE is cut, the base removed and the correct base inserted. In ESCHERICHIA COLI, delayed METHYLATION is used as a means of distinguishing the old (parental) DNA strand from the new (daughter) strand of the newly replicated DUPLEX. A METHYL TRANSFERASE ENZYME acts slowly after DNA REPLICATION to ensure that the daughter strand remains undermethylated, relative to the parent strand, for a while. This allows the repair system to recognize the daughter strand and replace the wrong base.
References in periodicals archive ?
New York, New York-based biopharmaceutical company Bristol-Myers Squibb (NYSE: BMY) has released new data from a cohort of the phase 2 CheckMate -142 trial evaluating Opdivo (nivolumab) and Yervoy (ipilimumab) for the treatment of patients with DNA mismatch repair deficient or microsatellite instability-high (MSI-H) metastatic colorectal cancer, the company said.
Bristol-Myers Squibb announced new data from a cohort of the phase 2 CheckMate -142 trial evaluating Opdivo and Yervoy for the treatment of patients with DNA mismatch repair deficient or microsatellite instability-high metastatic colorectal cancer.
Mutations of tumor suppressor genes TP53 (4) and pl6 (5); dysregulation of proto-oncogenes EGF, (6) EGFR, (7) TGF, (8) and HER2 (9); and loss of DNA mismatch repair function10,11 have all been described.
Anti-PD-1 antibodies are generally more effective in patients with a high frequency of microsatellite instability (MSI), a biomarker that results in dysfunctional DNA mismatch repair, and less effective in other patients.
Bristol-Myers Squibb Company today announced interim data from CheckMate -142, a Phase 2, multi-cohort trial evaluating Opdivo (nivolumab) monotherapy or in combination with Yervoy (ipilimumab) for the treatment of patients with DNA mismatch repair deficient (dMMR) or microsatellite instability-high (MSI-H) metastatic colorectal cancer (CRC).
1] Such DNA damage can be corrected by some DNA repair mechanisms such as base excision repair (BER), nucleotide excision repair (NER), double strand break repair (DSBR) and, DNA mismatch repair (DMR) which play a crucial role in maintenance of genomic integrity.
Such instabilities result from deficient function of DNA mismatch repair (MMR) genes, thus indicating a tendency toward increased genetic mutations [6-8].
Tumor biology studies established new chemoprevention for familial adenomatous polyposis syndrome and universal tumor screening guidelines based on DNA mismatch repair mutations and microsatellite instability for colorectal cancer in patients with Lynch syndrome.
Modrich's conclusion was that DNA mismatch repair is a natural process that corrects mismatches that occur when DNA is copied, recognizing the defect strand by its unmethylated state.
coli) (MLH1), (4) DNA mismatch repair protein Msh2 (MSH2), mutS homolog 6 (MSH6), mismatch repair endonuclease PMS2 (PMS2), and epithelial cell adhesion molecule (EPCAM), such as occurs in patients with Lynch syndrome, for whom more than 90% of colon cancers test MSI positive (1, 2).
Orans has extensive experience in DNA mismatch repair in hereditary colon cancer, bacterial fitness and pathogenesis in infectious disease, and brings expertise in using macromolecular crystallography to study the structural biology and biochemistry of proteins and nucleic acids.
Another autosomal-dominant disorder, hereditary nonpolyposis colorecstal cancer (HNPCC) syndrome arises as a result of a genetic defect in DNA mismatch repair mechanisms.