HPRT基因用于γ射线和苯并芘鉴别诊断的初步研究

A primary study on deletion of HPRT in differentiated diagnosis between γ ray and benzo-pyrene

为了解γ射线和苯并芘对细胞次黄嘌呤鸟嘌呤磷酸核糖基转移酶(hypoxanthine guanine phosphoribosyl transferase,HPRT)基因突变的影响,探索一种用于鉴别诊断γ射线和苯并芘引起的细胞损伤的早期检测敏感指标,采集了3名健康人血液,每人16 m L,分为16组,其中,10个组分别进行^(60)Coγ射线照射(0~5 Gy),另外6个组分别进行苯并芘染毒(0~10μg/m L),使用荧光定量聚合酶链式反应(quantitative polymerase chain reaction,q PCR)方法分析γ射线和苯并芘对细胞HPRT基因突变位点频率的变化情况,从而筛选γ射线和苯并芘对细胞损伤的HPRT差异突变位点。结果表明,0~5 Gy剂量范围内,HPRT的外显子2和外显子5突变频率随照射剂量增加而上调,通过拟合建立了突变频率与照射剂量间的剂量-效应直线方程,外显子2:y=0.360 3+0.110 68x,R2=0.99,p<0.01,外显子5:y=0.429 8+0.082 3x,R2=0.93,p<0.01;而0~10μg/m L苯并芘染毒后,HPRT基因的外显子2和外显子5突变频率随染毒浓度增加没有发生明显改变。γ射线所引起的外显子5突变频率与苯并芘相比有显著性差异(p<0.05),HPRT基因外显子5有望成为一种γ射线和苯并芘的鉴别点。

To investigate the changes of deletion of HPRT exposure to γ ray and benzo-pyrene,and to find a differential diagnosis index for cell injury induced by γ ray and benzo-pyrene human peripheral blood samples from three persons were exposed to^60）Co γ rays at 10 different doses（ 0—5 Gy） and benzopyrene at 6 different concentrations（ 0—10 μg / mL）,its DNA was isolated from white cell. The changes of deletion of HPRT exposure to γ ray and benzo-pyrene were detected by real time quantitative PCR.The relationship between deletion frequency of HPRT exon and irradiation dose represents certain linear correlation from 0—5 Gy. A linear regression equation has been obtained using statistics regression analysis software： exon- 2,y = 0. 360 3 ＋ 0. 110 68 x,R^2= 0. 99,p〈 0. 01; exon- 5,y = 0. 429 8 ＋0. 082 3x,R^2= 0. 93,p 〈0. 01 while,the relationship between deletion frequency of HPRT and different concentrations（ 0—10 μg / mL） represents no statistical significance. There is an obvious influence on deletion frequency of exon 5 of HPRT induced by γ ray,while there is no obvious influence on deletion frequency of exon 5 of HPRT induced by benzo-pyrene,which may be a new differential diagnosis index in the future.