Source:http://linkedlifedata.com/resource/umls/id/C1333233
NCI: DNA Mismatch Repair Protein MLH3, encoded by the MLH3 gene, is ubiquitously expressed in various tissues and two isoforms are produced by alternative splicing. MLH3 interacts with MLH1 and shares the same interacting region on MLH1 with PMS1 and PMS2. The balance of these three competing MLH1 partners might be important in the repair of mismatches in DNA. Malfunction of the mismatch repair system results in a mutator phenotype, which is manifested as microsatellite instability (MSI). MSI is often divided into 2 forms: MSI-high (MSI-H) and MSI-low (MSI-L), based quantitatively on the observed frequency of genomic mutations. An appreciable frequency of somatic MLH3 mutations in MSI-H tumors is consistent with a possible role for this gene in the progression of colorectal cancer tumorigenesis. Germline mutations of the MLH3 gene may also play a role in hereditary nonpolyposis colorectal cancer (NCI)