Interacting Gene/EnzymeAllele nameGenotype(s)Defining Change(s)Type(s)DescriptionDetailsCanalicular multispecific organic anion transporter 1ABCC2 IVS 23+56(C;C) / (C;T)T alleleADR Directly StudiedPatients with this genotype have increased risk of toxicity with methotrexate.DetailsMethylenetetrahydrofolate reductase---(T;T) / (C;T)T alleleADR Directly StudiedPatients with this genotype have increased risk of toxicity with methotrexate.Details