Objective: To detect JAK2 V617F mutation burden and its clinical implications in patients with myeloproliferative neoplasm (MPN).
Methods: JAK2 V617F mutation burden were detected by using MGB Taqman probes and its clinical significance were retrospectively studied in 415 MPN patients.
Results: JAK2 V617F was found in 56.9% of all patients [83.5% in polycythemia vera (PV), 55.9% in essential thrombocythemia (ET), 41.9% in primary myelofibrosis (PMF) and 64.7% in MPN-unclassifiable)]. The majority of patients carried heterozygous JAK2 V617F mutation and homozygote was found only in 12 cases (4 in PV, 4 in MPN-U, 2 in PMF, 1 in ET, and 1 in chronic neutrophilic leukemia). Most patients (68.8%) were lower mutation burden (mutation burden<50%), but PV had the highest burden, the moderate burden in PMF and the least in ET. The patient's age and WBC count were significantly correlated with higher mutation burden in PV. WBC count was significantly related to higher mutation burden in ET. WBC count, Hb level and the platelet count were significantly related to higher mutation burden in PMF.
Conclusion: The mutation burden of JAK2 V617F from high to low was PV, ET and PMF. The majority of JAK2 V617F mutation was heterozygous. JAK2 V617F mutation burden was positively correlated with age, WBC, Hb and platelet counts.
目的: 探讨JAK2 V617F突变负荷与骨髓增殖性肿瘤（MPN）的关系。
方法: 对415例MPN患者的临床资料进行回顾性研究，应用MGB Taqman探针PCR方法定量检测JAK2 V617F突变负荷，分析突变负荷与患者临床及实验室特征之间的相关性。
结果: 415例MPN患者中共检出236例（56.9%）JAK2 V617F突变阳性，其中109例真性红细胞增多症（PV）检出91例（83.5%），143例原发性血小板增多症（ET）检出80例（55.9%），74例原发性骨髓纤维化（PMF）检出31例（41.9%），51例MPN不能分类（MPN-U）检出33例（64.7%），1例慢性中性粒细胞白血病（CNL）为纯合突变，4例高嗜酸粒细胞增多症（HES）和33例慢性髓性白血病（CML）未发现突变。236例JAK2 V617F突变阳性患者中12例为纯合突变（其中PV、MPN-U各4例，PMF 2例，ET、CNL各1例）。JAK2 V617F突变以低突变负荷（突变负荷<50%）为主（68.8%）。突变负荷以PV组最大，PMF次之，ET最小。PV患者年龄、WBC与突变负荷呈正相关；ET患者WBC与突变负荷呈正相关；PMF患者WBC、HGB、PLT与JAK2 V617F突变负荷均呈正相关。突变负荷与MPN其他临床参数无明显相关性。
结论: JAK2 V617F突变负荷从高到低依次为PV、PMF和ET，突变状态以杂合突变为主，突变负荷随患者年龄、血红蛋白水平、白细胞及血小板计数升高而增加。