慢性骨髓增殖性疾病131例JAK2V617F突变的定量分析及临床意义

目的 研究JAK2V617F突变在慢性骨髓增殖性疾病(CMPD)中的发生率、突变类型、转录本水平及其临床意义.方法 采用突变特异性扩增系统(ARMS)-PCR方法 检测JAK2V617F的发生率及其突变类型;毛细管电泳方法 定量分析JAK2V617突变转录本水平.结果 纯合型JAK2V617F突变特发性血小板增多症(ET)患者和杂合型JAK2v617F突变ET患者其发病年龄均较野生型患者为高(P<0.05);CMPD患者发病年龄与JAK2V617F突变的发生问存在相关性(P<0.05),≥60岁患者的JAK2V617F突变转录本水平高于<60岁患者(P<0.05);JAK2V617F突变型CMPD患者中真性红细胞增多症(PV)和ET患者白细胞和血红蛋白水平均高于野生型患者(P<0.05),ET患者中纯合型突变者白细胞水平高于杂合型突变者(P<0.05);JAK2V617F突变在PV中的发生率和JAK2V617F纯合型突变在PV中的发生率均高于ET患者(P<0.05);JAK2V617F转录本水平均值在PV、ET和慢性特发性骨髓纤维化患者中无差别.结论 ARMS-PCR结合毛细管电泳定性和定量分析JAK2V617F突变可用于CMPD的诊断和预后判定.

The quantitative assay and clinical significance of JAK2V617F mutation in 131 patients with chronic myeloproliferative disorders

Objective To investigate the frequency and mutational status of JAK2V617F mutation in Chinese patients with chronic myeloproliferative disorders(CMPD) and to study the relative quantification of mutated JAK2 mRNA and the clinical significance. Methods JAK2V617F mutation and the mutational status were screened with amplification-refractory mutation system polymerase chain reaction(ARMS-PCR), the relative quantification of mutated JAK2 mRNA was studied by using capillary electrophoresis. Results A higher prevalence of JAK2V617F in either the heterozygotc or homozyote status in essential thrombocythemia (ET) was observed in elderly patients with ET (P<0.05). The presence of JAK2V617F was found to be significantly correlated with the age at diagnosis (P<0.05); patients with age ≥ 60 years showed significantly higher JAK2 mutated RNA levels than those with age < 60 years (P<0.05); the presence of JAK2V617F in polycythemia vera (PV) and ET was found to be significantly associated with higher hemoglobin level and higher leukocyte count (P< 0.05). In addition, higher leukocyte count was observed in homozygous ET patients than in heterozygous ET patients (P<0.05). The frequency of JAK2V617F mutation and the prevalence of homozygote in PV patients were higher than those in ET patients (P<0.05). The differences of JAK2V617F mRNA levels among PV, ET and chronic idiopathic myelofibrosis (IMF) were not significant. Conclusions ARMS-PCR technique can be used to detect the frequency and mutational status of JAK2V617F mutation owing to its sensitivity and along with capillary electrophoresis, quantitative assay for mutated JAK2 mRNA, diagnosis of CMPD and judgement of prognosis become possible.