Involved in DNA mismatch repair (MMR), correcting insertion-deletion loops (IDLs) resulting from DNA replication, DNA damage or from recombination events between non-identical sequences during meiosis. Component of a MutL heterodimer with MLH1, which probably forms a ternary complex with the MutSbeta heterodimer that initially recognizes the DNA mismatches. This complex is thought to be responsible for directing the downsteam MMR events, including strand discrimination, excision, and resynthesis. Plays a role in the repair of heteroduplex sites present in meiotic recombination intermediates and is involved in maintaining the genetic stability of simple sequence repeats by correction of frameshift intermediates. Heterodimer of MLH1 and MLH2. Present with 72 molecules/cell in log phase SD medium. Belongs to the DNA mismatch repair MutL/HexB family.