In terms of the codominant model, individuals with the AA genotype of the Bcl-2 gene had a greater vulnerability to leukemia with an odds ratio (OR) of 3.17 (95% confidence interval (CI): 1.33–7.53), a relative risk (RR) of 1.88 (95% CI: 1.09–3.25), with a significant p-value (<0.009). This evidence concerns the gene BCL2 and leukemia.