Normally, it is demethylated, whereas its methylation at 94–100% completely turns off MLH1 expression, thereby leading to microsatellite instability, Lynch syndrome, and hereditary predisposition to colorectal, uterine, and genitourinary cancers (CpG_11–CpG_18 are the most crucial) [40,41]. This evidence concerns the gene MLH1 and Lynch syndrome.