Analysis of recessive model showed significant difference for the individual genotype of GSTM1 (p = 0.008; OR: 0.46; 95% CI: 0.26–0.82), this suggests that individual genotype of GSTM1 null is associated with CML development. This evidence concerns the gene GSTM1 and chronic myelogenous leukemia, BCR-ABL1 positive.