GCSF gene is expressed but not rearranged in a patient with isochromosome 17q positive acute nonlymphocytic leukemia.

We describe a patient with acute nonlymphocytic leukemia (ANLL) and isochromosome 17q as the sole cytogenetic abnormality. ANNL with i(17q) may represent a distinct entity with certain clinical features, such as male sex, hepatosplenomegaly, and characteristic findings in bone marrow (BM) cytology, including hypercellularity, marked basophilia and eosinophilia, and massive increase in abnormal megakaryocytes. Molecular studies of peripheral blood (PB) cells of our patient, by polymerase chain reaction (PCR) analysis, showed expression of the GCSF gene, which is located on 17q. Southern blots hybridized with a GCSF probe showed no rearrangement of this gene as has been described in some patients with i(17q) positive chronic myeloid leukemia (CML).