Methylation-specific PCR shows ABL1 methylation patterns in clinical samples from acute-phase CML. NBC, normal donor buffy-coat DNA; SssI-NBC, CpG methylase (SssI methylase)-treated normal donor buffy-coat DNA; EM2, CML cell line EM2. Native DNA lane contains DNA that was not modified by bisulfite. M, primers specific for methylated DNA; U, primers specific for unmethylated DNA; ◊x, ◊x/HaeIII marker.