Misexpression of DNM1L and Mfn1/2 may underlie several human hematological malignancies including acute myeloid leukemia (AML), chronic myeloid leukemia (CML), chronic lymphocytic leukemia (CLL) and myelodysplastic syndromes1,2. The gene discussed is MFN1; the disease is B-cell chronic lymphocytic leukemia.