More than 98% of patients with APL have PML-RARα gene fusion, which is due to t (15;17) gene translocation, resulting in the fusion of promyelocytic leukemia (PML) on chromosome 15 with the gene encoding retinoic acid receptor-α (RARα) on chromosome 17, producing the fusion protein PML-RARα, which prevents cancer cell apoptosis [6, 7]. The gene discussed is PML; the disease is cancer.