PMS2 and cancer: It is caused by heterozygous germline disease-causing variants (DCVs) in the DNA mismatch repair (MMR) genes: MLH1,MSH2,MSH6,PMS2 or by deletions in EPCAM. It has recently become clear that defects in each of the LS-associated genes give rise to a distinct entity with a unique pathogenesis, different lifetime cancer risks [2], and mean age at diagnosis [3].