Considering which amino acid (isoleucine or threonine) was present at position 80 of the HLA-Bw4 molecule, the KIR HLA-B ligand genotype HLA-Bw4Thr80 Thr80was significantly more prevalent in CML and AML compared to the control group (16.7% CML, p=0.04, OR 16.4 [95% CI: 1.0-5.07] and 13.0% AML, p=0.01 OR 12.3 [95% CI: 1.0-3.24] vs. 1.2% in healthy controls). This evidence concerns the gene KIR3DL1 and chronic myelogenous leukemia, BCR-ABL1 positive.