APEX1 and colorectal carcinoma: The first thing worth noting is the increased risk of CRC in the case of co-occurrence of genotype 51Gln/His of APEX gene with 64Val/Val of APEX gene when compared to risk associated only with 51Gln/His (OR 2.266 (1.120–4.585); p = 0.022 versus 1.706 (1.174–2.480); p = 0.005) and similar increased risk of CRC in the case of co-occurrence of genotype 51Gln/His of APEX gene with 689Arg/Arg ERCC4 (OR 2.464 (1.247–4.870); p = 0.009 versus 1.706 (1.174–2.480); p = 0.005).