Guibal et al. reported that Cebpa+/- mice did not develop leukemia nor present abnormal cell counts, but double mutants human cathepsin G (hCG)-PML/RARA Cebpa+/- developed APL at a higher frequency, decreased latency, and had a significantly shorter survival rate than hCG-PML/RARA TM. The gene discussed is RARA; the disease is leukemia.