MLH1 and colorectal carcinoma: CRC tumour samples from the primary (mean β = 0.77 ± 0.06 SD) and secondary (0.74 ± 0.16) MLH1 epimutation carriers showed MLH1 methylation levels (i.e. hypermethylation) consistent with tumour samples from people with sporadic MLH1 methylated CRCs (0.55 ± 0.09).