JAK2 V617F ALLELE BURDEN IN CHRONIC MYELOPROLIFERATIVE DISEASES

Abstract

BACKGROUND Chronic myeloproliferative disorders (CMPD) are a group of conditions affecting thestem cell causing over-production of one or more of the blood cells. The presence ofPh chromosome distinguishes chronic myeloid leukemia (CML) from other diseases of thegroup. JAK2 V617F mutation is present in 76–97 % of patients with polycythaemia vera(PRV), 29–75 % of patients with essential thrombocythaemia (ET) and 50 % of patientswith chronic idiopathic myelofibrosis (CIMF). The JAK2 V617F allele burden correlateswith the clinical picture of the diseases. METHODS We involved 110 patients with ET, PRV and CIMF in whom we already had extracted DNAsamples from granulocytes. We established the JAK2 V617F allele burden in the DNA ofgranulocytes by using real-time polymerase chain reaction (RQ-PCR). RESULTS The mean allele burden of JAK2 V617F is 25 % in patients with ET, 47 % in patients withPRV and 85 % in patients with CIMF. There is a statistically significant correlation betweenthe allele burden and the number of leukocytes in peripheral blood.Conclusion The mean allele burden of JAK2 V617F is different in ET, PRV and CIMF. It is plausible thatthe three seperate diseases are only different clinical pictures of the same CMPD dependingon the allele burden. The allele burden strongly correlates with the peripheral blood count