KIR3DL1 and leukemia: Additionally, HLA polymorphism has a stronger effect in leukemia susceptibility than KIR. This conclusion is also supported by another study, which showed only a trend of association for the presence of five or six activating KIR genes (p = 0.06), but a strong association for the presence of Bw4 (OR = 0.56; p = 0.005) in CLL patients (Karabon et al., 2011).