Prevalence of JAK2 V617F mutation in Indian patients with chronic myeloproliferative disorders.

BACKGROUND & OBJECTIVES The Janus-associated Kinase-2 mutation JAK2 V617F in chronic myeloproliferative disorders (CMPDs) has been described as a frequent genetic event in majority of patients with polycythemia vera (PV), essential thrombocythemia (ET) and idiopathic myelofibrosis (IMF). Its frequency varies in different populations but there are no data from India. We therefore, looked for JAK2 V617F mutation in Indian patients with chronic myeloproliferative disorders. METHODS Mutation screening for JAK2 V617F in patients with polycythemia vera, essential thrombocythemia and idiopathic myelofibrosis was performed in 75 patients attending Haematology clinic in a tertiary care hospital in north India, by polymerase chain reaction and restriction enzyme-based assay. RESULTS JAK2 V617F mutation was found in 51 of 75 cases (68%) of CMPD, 82 per cent in PV, 70 per cent in ET and 52 per cent of IMF. The presence of JAK2 V617F mutation was associated with a higher haemoglobin level (P<0.05), a higher white blood cell count (P<0.01) and higher age (P<0.05). INTERPRETATION & CONCLUSION The JAK2 V617F mutation was detected in 86 per cent of patients with CMPD disorders. Peripheral blood mutation screening for JAK2 V617F can be incorporated into the initial evaluation of patients suspected to have CMPD.