TCF7L2 and adenoma: In fact, a somatic second hit in the APC gene was found in most adenomas (72%) and a small fraction of sequenced adenomas also had further somatic mutations in Wnt signaling pathway components including TCF7L2. Damaging somatic mutations on KRAS and FBXW7 genes also occurred, as well as potential deleterious mutations in additional genes including CNOT3, EWSR1 and PCMTD1 (Table 1).