ABCC1 and colorectal carcinoma: Furthermore, the presence of the intron variants ABCC1 rs17501011 (c.49-20550G>A), CES1 rs9921399 (c.52+538A>G), UGT1A rs1113193 (c.855+41929G>A for UGT1A8 and c.855+23114G>A for UGT1A10) was related to lower OS in FOLFIRI-treated CRC patients [180].