The prevalence of methylated (MM) and hemi-methylated (MU) CpG dinucleotides within the APAF-1 gene promoter of AML patients was 12 (11.9%) and 45 (44.6%), respectively, while no methylation was detected in the control samples (p < 0.0001). This evidence concerns the gene APAF1 and acute myeloid leukemia.