MLH1 and colorectal carcinoma: As evident from Fig. 3, gene methylation percentage was remarkably higher in S-MSI compared with the other three CRC classes (p < 0.0001) and it was positively correlated with MLH1 methylation (p < 0.0001) and with high levels of LINE-1 methylation (L1 and L2 clusters) (p = 0.006).