ABCB1 and colorectal carcinoma: The aim of the present French, carefully paired case-control study was to re-evaluate and hierarchize all these potential genetic risk factors of CRC, namely polymorphisms in UGT1A6–9, UGT2B7, ABCB1, ABCC2, SLCO1B1 and SLCO2B1, taking into account the main environmental risk factors as pairing criteria of stratification factors.