ABCA1甲基化及表达水平在回汉族AS人群中的变化及其诊断价值

Diagnostic Value and Variations both ABCA1 DNA Methylation and Its Expression between Hui and Han Patients with AS in Ningxia

目的本研究探讨宁夏回汉族动脉粥样硬化(atherosclerosis,AS)患者外周血ATP结合盒转运蛋白A1(ABCA1)基因表达水平及其甲基化状态,并探讨其在AS发生、发展中的意义及诊断价值。方法选择经颈动脉多普勒超声确诊的回族AS组50例,回族对照组53例,汉族AS组55例,汉族对照组44例;采用实时荧光定量PCR(qRT-PCR)检测外周血ABCA1 mRNA的表达,巢式降落式甲基化特异性PCR(nt-MSP)检测外周血ABCA1基因DNA启动子区甲基化程度。结果 ABCA1 mRNA相对表达水平,回族AS组比汉族AS组低13.21%(P<0.05),回族AS组比回族对照组低14.81%(P<0.05),汉族AS组比汉族对照组低20.89%(P<0.05);ABCA1基因甲基化水平,回族AS组高于汉族AS组(P<0.05),汉族AS组高于汉族对照组(P<0.05),回族AS组高于回族对照组(P<0.05),回族对照组高于汉族对照组(P<0.05)。ROC分析结果,ABCA1甲基化水平在回族AS组和汉族AS组中的最佳诊断点分别为0.498、0.428,ROC曲线下面积分别为0.649、0.665,灵敏度和特异度分别为91.7%、88.9%。结论回汉族AS患者外周血中ABCA1基因甲基化水平存在差异,回族人群ABCA1基因甲基化基础水平比汉族高,ABCA1 mRNA的表达水平比汉族低,ABCA1甲基化在诊断AS中有较好的价值。

Objective To investigate both the expression and the methylation status involved ABCA1 and to explore its significance and diagnostic value in AS. Methods 50 Hui AS patients,53 Hui ethnic controls,55 Han AS patients and 44 Han ethnic controls,were confirmed by carotid artery Doppler ultrasound. ABCA1 mRNA expression were determined by real- time reverse transcription- polymerase chain reaction( qRT-PCR). The methylation status of ABCA1 gene promoter region was monitored using the nest tounchdown methylation specific polymerase chain reaction( nt- MSP). Results In comparison with Han ethnic AS group,ABCA1 mRNA expression in Hui ethnic AS group reduced significantly by 13. 21%( P < 0. 05). Compared with Hui ethnic control group,ABCA1 mRNA expression in Hui ethnic AS group decreased by 14. 81%( P <0. 05). Its expression in Han ethnic AS group was 20. 89% and it was lower than that in Han ethnic controls group( P < 0. 05). ABCA1 methylation value,in Hui AS group was significantly higher than in Hui control group,in Han ethnic AS group was significantly higher than in Han ethnic control group,in Hui ethnic control group was significantly higher than Han ethnic control group( P < 0. 05). Its methylation value in Hui ethnic AS group was significantly higher than that in Hui ethnic control group( P < 0. 05). Receiver operating characteristic( ROC) analysis showed that a cutoff for Hui ethnic patients and Han ethnic patients with AS were0. 498,0. 428 respectively while the sensitivity and specificity were 91. 7%,88. 9% respectively. Its area under the curve( AUC) were 0. 649,0. 665 respectively. Conclusion There was a significant difference of ABCA1 methylation value between Hui ethnic AS group and Han ethnic AS group. The basic methylation value of peripheral blood ABCA1 in Hui ethnic subjects was significantly higher than Han ethnic subjects. Moreover,there was a probability that ABCA1 methylation regulated its mRNA expression through inhibiting the transcription of ABCA1 promoter. ABCA1 methylation was found to have a diagnostic value in AS patients.