DNA甲基化调控肺动脉病理重构及早期预警分析

The pathogenesis of pulmonary arterial hypertension (PAH) remains unclear. BMPR2 is identified as the major predisposing gene for PAH, and carriers of BMPR2 mutation are at high risk of developing PAH. However, low penetrance and high heterogeneity make it hard to predict whether carriers will develop PAH through genetic counseling screening. Our preliminary experiments showed DNA methylation was involved in pulmonary vascular remodeling. By comparing the methylation of affected and unaffected BMPR2 mutation carriers, we have found several differentially methylated regions. Using methylation genotyping, we can identify high-risk carriers and make early warning, with specificity and sensitivity of both greater than 80%. Based on these studies, we will establish a bio-bank and a clinical database of high-risk PAH population, construct induced pluripotent stem cells and lymphocyte cell lines, develop clinical assay kits for clinical testing, and verify the predictive value of DNA methylation genotyping in PAH early warning. We will also identify the interaction of modifier genes and BMPR2 and explore the function and mechanisms of DNA methylation in PAH using genetic modified rat models. Our research will help to understand the integral functions of genetics and epigenetics in the pathogenesis of PAH, establish a novel network between genetics, epigenetics, and PAH phenotype, identify novel pathogenic targets, and develop methods of early warning and new treatment strategies for PAH.

肺动脉高压（PAH）发病机制尚未完全阐明。BMPR2是目前已知PAH最主要致病基因，但目前无法仅依靠遗传筛查准确判断BMPR2基因突变携带者将来是否发生PAH。我们在前期工作中发现DNA甲基化参与PAH血管重构，并筛选出多个BMPR2修饰基因，其甲基化分型可协助BMPR2突变携带者进行早期预警，特异性和敏感性均超过80%。在此研究基础上，我们将建立PAH高危人群生物样本库和临床数据库，构建多能诱导干细胞和淋巴细胞株，验证DNA甲基化分型在PAH预警的作用，研发临床检测试剂盒；构建修饰基因转基因和基因敲除大鼠，联合BMPR2基因敲除和基因敲入大鼠模型，研究修饰基因与BMPR2交互作用，探讨DNA甲基化在PAH中的功能和机制。我们研究将从表观遗传水平解释PAH发生发展机理，构建遗传、表观遗传、PAH临床表型三者之联系，发现新PAH致病靶点，为PAH早期预警和开发新的治疗方法提供手段。

肺动脉高压是一类以肺动脉压力增高为主要特征的致命性疾病，其发病机制不明，治疗棘手，预后恶劣。本研究聚焦于DNA甲基化调控肺动脉病理重构及早期预警分析，是一个全新的探索。在研期间：1.2018年，我们完成了首个中国人PAH全基因组遗传学研究，继而发现两个新的中国人PAH疾病相关基因：BMP9和PTGIS；2.首次发现DNA甲基化是肺动脉高压发病新机制，全面揭示了DNA甲基转移酶DNMT3B改善PAH肺血管重构的作用及机制，证实了DNMT3B是PAH发病过程中的新型调节介质，上调DNMT3B的表达有望成为治疗PAH的潜在靶点；3.发现精胺合成酶可能成为PAH治疗的又一新靶点；4.证实了microRNA-483在PAH发病中的重要保护作用，为临床诊断治疗PAH提供了新的思路与依据；5.更重要的是，我们从零起步，创建了iPSCs培养平台，构建了BMPR2、PTGIS、ALK1等多种罕见突变患者来源的iPSCs库；通过临床样本采集、手术及尸检等多种方式，创立了PAH患者样本库，为进一步研究功能、探索机制打下坚实基础。