Tumor-specific methylation was found in a CRC and small bowel cancer for 2 PMS2 carriers, and constitutional methylation of MLH1 was found in 1 individual with EC who met the Amsterdam I criteria (see Supplementary Figures 2 and 3, Supplementary Digital Content 1, http://links.lww.com/CTG/A667). Here, MLH1 is linked to colorectal carcinoma.