This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Misc. (W.B.C), Subject name: Pathology
[{'content': 'BCR-ABL fusion gene is detected by? \nSelect and explain. \nA. Flow cytometry, B. FISH, C. Karyotyping, D. RT-PCR', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (b) FISH(Ref: Robbins 9th/pg 616-618)Flow cytometry: is used for immunophenotyping in Leukemias & LymphomasFISH- used for detecting submicroscopic chromosomal aberrations of BCR-ABL fusionKaryotyping: Used for detecting chromosomal defects of at least 5 mb size (low sensitivity)RT-PCR: used for quantitative DNA estimation', 'role': 'assistant'}]