MRC1 and colorectal adenoma: Recent meta-analyses have found that 69.5% (614/883; 95% CI: 66.4–72.6) to 76.7% (491/640; 95% CI: 73.3–79.9) of LS colorectal adenomas are MMR deficient [67,244], much higher than the 2.8% (60/2119; 95% CI: 2.2–3.6) of colorectal adenomas from the general population [244].