As previously demonstrated, in patients with adeno-colorectal cancer treated with a 5-FU and oxaliplatin schedule, the GSTP1 Ile105Val heterozygous status was related with an augmented risk of neuropathy, while patients with Val/Val status had a lower neurotoxicity risk profile and tumor aggressiveness than Ile/Ile phenotypes (Ruzzo et al., 2007). The gene discussed is GSTP1; the disease is neoplasm.