Chromosomal abnormalities play an important role in genesis of Acute Lymphoblastic Leukemia and have prognostic implications. This work is aimed at detecting common chromosomal translocation and associated fusion oncogenes in adult ALL patients and their relationship with clinical features and treatment outcome by using RT-PCR and interphase FISH. Five most common fusion oncogenes i.e. BCR-ABL, ETV6-RUNX1, MLL-AF4, SIL-TAL1 and TCF3-PBX1, were found in 79 percent of the patients in the sample. BCR-ABL and MLL-AF4 characterized a subset of adult ALL patients with aggressive clinical behavior...