This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Blood, Subject name: Pathology
[{'content': "JAK-2 mutation is strongly associated with? \nSelect and explain. \nA. Burkitt's lymphoma, B. Polycythemia vera, C. Multiple myeloma, D. Mantle cell lymphoma", 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Polycythemia vera * Janus kinase 2 (JAK2), a member of the Janus kinase family, is a non-receptor tyrosine kinase.* JAK2 fusions with the TEL(ETV6) (TEL-JAK2) and PCM 1 have found to be associated with leukemia, particularly clonal eosinophilia forms of the disease.* JAK-2 mutations are associated withi) Polycythemia vera,ii) Essential thrombocythemiaiii) Myelofibrosis (and other myeloproliferative disorders)iv) Abnormal heart defects", 'role': 'assistant'}]