N-RAS GENE POINT MUTATIONS IN BRAZILIAN ACUTE MYELOGENOUS LEUKEMIA PATIENTS CORRELATE WITH A POOR-PROGNOSIS

The frequency of ras gene mutations varies from 11 to 27% in AML popul ations from the United States and Europe but it seems that there is no study regarding the frequency of mutated N-ras gene in patients with AML in South America. In order to study the frequency of N-ras gene mu tations (exons 1 and 2) in Brazilian patients with AML and to evaluate the possible correlation between the presence of the mutation and cli nical features, 40 patients were analyzed. N-ras mutations were identi fied in DNA samples from eight of 40 AML patients (20%). No significan t correlation was found between N-ras mutation and age, sex, race, res ponse to therapy, FAB subtype or occupational exposure. However, the o verall survival and AML-free survival were significantly shorter in pa tients with N-ras mutations than in those without these abnormalities.