The frequency of SLIT2 hypermethylation was markedly increased with the progression of clinical stage, that is, it was the lowest in CML-CP samples (12/80, 15%), higher in CML-AP samples (4/8, 50%) and the highest in CML-BC samples (11/16, 69%) (P < 0.001, Table 1). This evidence concerns the gene SLIT2 and chronic myelogenous leukemia, BCR-ABL1 positive.