In summary, the cumulative evidence, including a comprehensive genome-wide association study (GWAS) of imputed rare variants in hereditary adenomatous polyposis syndrome genes [86], suggests that monoallelic PVs in the recessively inherited genes MUTYH, NTHL1, MSH3, and MBD4 do not increase the risk of CRC or polyposis. This evidence concerns the gene MBD4 and polyposis.