MSH2 and Lynch syndrome: There are four Lynch syndromes that arise due to a constitutional (germline) pathogenic (or likely pathogenic) variant in one of the DNA mismatch repair (MMR) genes: MSH2, MLH1, MSH6, and PMS2 or by deletion of the 3′ end of the EPCAM gene, which results in hypermethylation of the MSH2 promoter (Ligtenberg et al., 2009).