The bone marrow aspirate was consistent with AML, and cytologic studies indicated an abnormality in FGFR1. Additional cytologic studies and fluorescence in situ hybridization (FISH) confirmation identified a t(8;22) clone, which was consistent with a BCR–FGFR1 translocation (Fig. 2A). This evidence concerns the gene FGFR1 and acute myeloid leukemia.