| umls-concept:C0210994 | skos:definition | NCI: DNA Mismatch Repair Protein MSH3, encoded by the MSH3 gene (MutS family), is a 127-kD mismatch repair (MMR) protein. Mismatch recognition in human cells is mediated by two heterodimers, MutS alpha (MSH2/MSH6) and MutS beta (MSH2/MSH3) with different mispair recognition properties and abilities. Both participate in repair of a dinucleotide insertion-deletion heterology but only MutS alpha restores base-base mismatch repair and shoulders primary responsibility for mismatch correction during replication. Predisposition to intestinal cancer requires loss of function of both Msh2/Msh6 and Msh2/Msh3 but Msh3 deficiency alone does not cause cancer predisposition. Mismatch repair deficiency can arise not only through mutation or transcriptional silencing of a mismatch repair gene, but also as a result of imbalance in the relative amounts of the MSH3 and MSH6 proteins because MutS alpha and MutS beta share a common component, MSH2. (NCI) | lld:umls |
