GSTP1 and colorectal carcinoma: Namely, the GSTM1-null genotype increased the risk of mortality by 1.79 times (p = 0.04), while the GSTP1-variant genotype was associated with a 1.57 times higher mortality risk in CRC patients (p = 0.035) in comparison to the reference GSTM1-active and GSTP1-referent IleIle genotypes, respectively (Table 4).