All MBD4-deficient adenomas (those that underwent WES and one additional adenoma from WEHI-2 that was targeted sequenced; see also Table S2 and the supplemental methods) harbored somatic driver mutations in APC with a significant enrichment of the CpG>TpG transition (GenBank: NM_000038.4: c.4348C>T) resulting in p.Arg1450∗, compared with sporadic adenomas and CRCs (Fisher’s exact; p < 0.00001; Figure 2F). Here, APC is linked to adenoma.