DISEASE CHARACTERISTICS: Diagnosis of any of the following: Chronic myelogenous leukemia (CML) in first chronic phase Myelodysplastic syndrome Refractory anemia with excess blasts (RAEB) RAEB in transformation Secondary leukemias untreated or in complete remission 1 (CR1) Acute myeloid leukemia in complete remission 2 (CR2) Acute lymphocytic leukemia (ALL) in CR2 High-risk acute leukemia in CR1 Ph+ ALL in CR1 or consolidation after induction chemotherapy Must qualify for allogeneic bone marrow transplantation (BMT) No HLA-matched, sibling donor for BMT available No current CNS disease No history of more than 2 episodes of active CNS disease