A system for the identification and correction of base-base mismatches, small insertion-deletion loops, and regions of heterology that are present in duplex DNA formed with strands from two recombining molecules. Correction of the mismatch can result in non-Mendelian segregation of alleles following meiosis.

The removal of nonhomologous sequences at the broken 3' single-strand DNA end before DNA repair synthesis can occur.

The removal of nonhomologous sequences at the broken 3' single-strand DNA end before DNA repair synthesis can occur.

A system for the correction of errors in which an incorrect base, which cannot form hydrogen bonds with the corresponding base in the parent strand, is incorporated into the daughter strand. The mismatch repair system promotes genomic fidelity by repairing base-base mismatches, insertion-deletion loops and heterologies generated during DNA replication and recombination.

Any process in which a new genotype is formed by reassortment of genes resulting in gene combinations different from those that were present in the parents. In eukaryotes genetic recombination can occur by chromosome assortment, intrachromosomal recombination, or nonreciprocal interchromosomal recombination. Interchromosomal recombination occurs by crossing over. In bacteria it may occur by genetic transformation, conjugation, transduction, or F-duction.

The cell cycle process in which genetic information is transferred from one helix to another. It often occurs in association with general genetic recombination events, and is believed to be a straightforward consequence of the mechanisms of general recombination and DNA repair. For example, meiosis might yield three copies of the maternal version of an allele and only one copy of the paternal allele, indicating that one of the two copies of the paternal allele has been changed to a copy of the maternal allele.

The exchange, reciprocal or nonreciprocal, of genetic material between one DNA molecule and a homologous region of DNA that occurs during mitotic cell cycles.

Repression of transcription at silent mating-type loci by alteration of the structure of chromatin.

Removal of a DNA interstrand crosslink (a covalent attachment of DNA bases on opposite strands of the DNA) and restoration of the DNA. DNA interstrand crosslinks occur when both strands of duplex DNA are covalently tethered together (e.g. by an exogenous or endogenous agent), thus preventing the strand unwinding necessary for essential DNA functions such as transcription and replication.

Any process that stops, prevents, or reduces the frequency, rate or extent of DNA replication by impeding the progress of the DNA replication fork. Replication fork arrest is one of the 'quality control' processes ensuring that DNA-dependent DNA replication occurs correctly. DNA replication fork arrest during DNA-dependent DNA replication is not known to occur outside of cases where a replication error needs to be prevented or corrected.

A chromosome that encodes the nuclear genome and is found in the nucleus of a eukaryotic cell during the cell cycle phases when the nucleus is intact.

A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.

A heterodimer involved in the recognition and repair of base-base and small insertion/deletion mismatches. In human the complex consists of two subunits, MSH2 and MSH6.

A heterodimer involved in binding to and correcting insertion/deletion mutations. In human the complex consists of two subunits, MSH2 and MSH3.