携带Rep1风险位点的帕金森病患者血液mRNA表达差异研究

Study on the differential expression of mRNA in blood of patients with Parkinson's disease carrying the Rep1 risk locus

目的探索携带SNCA基因（synuclein alpha）Rep1风险位点的帕金森病（Parkinson’s disease,PD）患者外周血基因表达差异。方法采用聚合酶链反应（Polymerase Chain Reaction,PCR）结合直接测序法检测128例维吾尔族帕金森病人（PD组）及160例维吾尔族健康体检者（对照组）SNCA启动子区Repl多态性,并按照PD患者年龄差异进行分组比较,年龄≤50岁为EOPD组,年龄〉50岁为LOPD组。进一步筛选携带Rep1风险位点的3例PD患者及3例非携带健康体检者,用Trizol提取外周血总RNA,分别与Illumina表达谱芯片进行杂交实验。结果EOPD组与年龄相匹配的对照组比较,Rep1位点CA碱基重复12次（2型等位基因）的频率分别为21.4%、6.9%,差异具有统计学意义（χ2=12.67,P=0.00）。与对照组比较,EOPD患者外周血中差异表达2倍以上的基因有359条,包括SNCA基因在内的122条表达上调2倍以上。其中与SNCA基因表达异常有关的多巴胺代谢和胆碱能突触信号通路改变最显著（FE=3.64,P=0.046;FE=5.57,P=0.005）。结论 Repl位点2型等位基因与EOPD的发生有关,携带该位点2型等位基因患者外周血SNCA表达异常升高。

Objective To explore the differences of gene expression in peripheral blood of patients with Parkinson＇s disease（ PD） carrying the synuclein alpha gene Rep1 risk locus. Methods Rep1 polymorphism of SNCA in promoter region was detected in 128 patients（ PD group） and 160 healthy volunteers（ control group） at the Repl promoter region of the Uyghur healthy volunteers（ control group） in cases,with the methods of Polymerase Chain Reaction（ PCR） and Direct Sequencing. Group comparison was based on age differences that the patients less than50 years as the EOPD group and the patients older than 50 years as LOPD group. Screening of 3 PD patients with Rep1 risk loci and 3 healthy controls,the total RNA was extracted from peripheral blood by Trizol,and the Illumina expression profile microarray was used for hybridization experiment. Results 2 allele frequency of 21. 4 % in EOPD group was significantly higher than that in the control group under 50 years old of 6. 9 %,which the difference was statistically significant（ χ~2= 12. 67,P = 0. 00）. By using this DNA microarray technology,359 candidate genes in patients with PD were found. 122 genes expressions correlating to PD were found with twice fold over-expression differences,compared with the control group. In which the changes that were involving in the dopaminergic and cholinergic synaptic signaling pathways were most significant（ FC = 3. 64,P = 0. 046; FC = 5. 57,P =0. 005）. Conclusion The allele of Repl locus 2 was related to the occurrence of EOPD,and SNCA gene expression was abnormally increased in peripheral blood of patients with type 2 alleles.