To validate these findings in primary human AML cells, we performed immunofluorescence studies using an antibody directed against the C-terminus of MYH11 (not detected in normal hematopoietic cells, and therefore specific for CBFB::MYH11) and an antibody that detects RUNX1, 2, and 3. The gene discussed is RUNX1; the disease is acute myeloid leukemia.