Mutation of CEBPA in familial acute myeloid leukemia.

We describe a family in whom three members affected by acute myeloid leukemia (AML) had an identical, 212delC mutation in CEBPA, the gene encoding the granulocytic differentiation factor C/EBPalpha. Unaffected family members did not have this mutation. Latent periods of 10, 18, and 30 years elapsed before the onset of overt leukemia in the three patients. One of them had a second CEBPA mutation, but only at the time of diagnosis. All three patients are currently well, with no abnormalities in the bone marrow. CEBPA mutation is apparently the primary event in the development of AML in this family.