[Oncogene activation in the leukemias].

Retroviral oncogenes are derived in evolution from normal cellular genes termed proto-oncogenes. This discovery has prompted the question whether human tumor cells show alteration of proto-oncogenes. Alteration found in leukemias (gene amplification, translocation and point mutation) are briefly discussed. The genes termed myc, abl, ras are involved. A case of acute myeloblastic leukemia with a point mutation in the N-ras gene is briefly discussed.