JAK2 V617F mutation in BCR-ABL negative patients with myeloproliferative disorder and its clinic significance.

Objective:To examine JAK2 V617F mutation in BCR-ABL negative patients with myeloproliferative disorders(MPD) and its relationship with clinical characteristics of MPD.Methods:Fifty-six BCR-ABL negative MPD patients(who had been diagnosed in the Provincial Hospital Affiliated to Shandong University) were included in the present study.The patients included 20 with polycythaemia vera(PV),26 with essential thrombocythaemia(ET) and 10 with idiopathic myelofibrosis(IMF).JAK2 V617F mutation in MPD patients was detected by allele-specific polymerase chain reaction(AS-PCR) and DNA-sequencing,and its correlation with clinical characteristics of MPD was analyzed.Results:JAK2 V617F mutation was detected in 36 of the 56 BCR-ABL negative MPD patients,including 17(17/20,85%) with PV,14(14/26,53.8%) with ET,and 5(5/10,50%) with IMF.The leukocyte(P=0.018) and platelet counts(P=0.021) were significantly different between JAK2 V617 positive and negative MPD patients in PV group;the leukocyte counts(P=0.001) and hemoglobin(P=0.007) were significantly different in ET group;and the leukocyte counts were significantly different(P=0.026) in IMF group.Significant difference was also found in the incidences of bleeding,thrombosis between JAK2 V617 positive and negative patients in ET group(P=0.016),but not in PV or IMF group.Conclusion:AS-PCR is a sensitive and reliable technique in detecting JAK2 V617F mutation.The clinical characteristics of JAK2 V617F mutantion positive MPD patients are different from those without the mutation.