ERCC2 and colorectal carcinoma: Two important recent meta-analyses - one by Zhang et al. (2014) on 11 case-control studies (including a total of 3 2,961 cases and 4,539 controls) and another by Zhang et al. (2011) on 15 case–control studies (including a total of 3,042 cases and 4,627 controls) did not found any evidence of a link between the XPD Lys751Gln polymorphism and risk of CRC.