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MLH1 mutL homolog 1

Gene ID: 4292, updated on 28-Nov-2023
Gene type: protein coding
Also known as: FCC2; COCA2; HNPCC; MLH-1; hMLH1; HNPCC2; LYNCH2; MMRCS1


The protein encoded by this gene can heterodimerize with mismatch repair endonuclease PMS2 to form MutL alpha, part of the DNA mismatch repair system. When MutL alpha is bound by MutS beta and some accessory proteins, the PMS2 subunit of MutL alpha introduces a single-strand break near DNA mismatches, providing an entry point for exonuclease degradation. The encoded protein is also involved in DNA damage signaling and can heterodimerize with DNA mismatch repair protein MLH3 to form MutL gamma, which is involved in meiosis. This gene was identified as a locus frequently mutated in hereditary nonpolyposis colon cancer (HNPCC). [provided by RefSeq, Aug 2017]

Copy number response

Copy number response

Sufficient evidence for dosage pathogenicity (Last evaluated 2021-10-13)

ClinGen Genome Curation PagePubMed

No evidence available (Last evaluated 2021-10-13)

ClinGen Genome Curation Page

Genomic context

Chromosome: 3; NC_000003.12 (36993466..37050846)
Total number of exons:


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