DNA mismatch repair, microsatellite instability and cancer.
Mismatch (MMR) repair system plays a significant role in restoration of stability in the genome. Mutations in mismatch repair genes hamper their activity thus bring about a defect in mismatch repair (MMR) mechanism thereby conferring instability in the microsatellite sequences of both the coding and non-coding regions of the genome. Mutated mismatch repair genes result in the expansion or contraction of microsatellite sequence and confer microsatellite unstable or replication error positive phenotype. Hypermethylation of promoter regions of some of the MMR genes also causes inactivation of these genes and thus contribute to MSI. Microsatellite instability is an indicator of MMR deficiency and is a prime cause of varied tumorogenesis.
Vaish
Minal
M
Department of Medical Genetics, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Raebareli Road, Lucknow 226 014, India.
Mittal
B
B
D000818:Animals; D020137:Base Pair Mismatch / Q000235:genetics*; D004249:DNA Damage; D019175:DNA Methylation; D004260:DNA Repair; D004261:DNA Replication; D006801:Humans; D019656:Loss of Heterozygosity; D018895:Microsatellite Repeats; D009154:Mutation; D009369:Neoplasms / Q000175:diagnosis / Q000235:genetics* / Q000628:therapy; D010641:Phenotype