As a matter of fact, even if scattered, some AML3 cells were focally positive for intracytoplasmic HMB45 (Fig 1B and 1B’), and AML4 cells were focally positive for Melan-A antigen (Fig 1C and 1C’), which is consistent with the AML phenotype. The gene discussed is RUNX2; the disease is acute myeloid leukemia.