Both the high number of GAA sites in the  APC gene compared to other key tumorgenesis genes frequently involved in other cancers [23], as well as the considerable exposure to ROS in the gastrointestinal tract, could be part of the explanation of why germline MUTYH mutations, and subsequently somatic APC mutations, are associated with development of particularly CRC [23]. The gene discussed is APC; the disease is colorectal carcinoma.