TCF7L2 and cancer: Already some normal cells have several mutations in cancer-related genes listed in the COSMIC database [27], such as N-54 (a mutation in TCF7L2), N-67 (mutations in TRRAP, TP53), N-102 (a mutation in KRAS), N-103 (a mutation in TP53), and N-111 (a mutation in GATA1), and one unlisted one in EYS.