MLH1, MSH2, MSH6 and PMS2 account for 40, 34, 18, and 8 %, respectively, of the 3000 unique germline sequence variants of MMR genes deposited to the International Society for Gastrointestinal Hereditary Tumours (InSiGHT) database ([16] and www.insight-group.org, date accessed December 19th, 2015). Here, MRC1 is linked to neoplasm.