ABCC4 and colorectal carcinoma: With the exception of a two-phase case-control study in a Spanish population [22] no previous study inquired the role of common genetic variants in MRP4 and PGT coding genes (ATP-Binding Cassette Sub-Family C Member 4 (ABCC4) and solute carrier organic anion transporter family, member 2A1 (SLCO2A1), respectively) in CRC genesis.