The Molecular Genetics of Venous Thromboembolic Disease

项目摘要 在美国，VTE每年影响90万人，具有高度的遗传性，约60%的终生风险可归因于 遗传因素。到目前为止，只有50%的遗传因素被描述为VTE。最近， VTE的全基因组关联研究(GWAS)已经证实了常见的VTE变种的贡献 凝血因子V(F5)和常见血型抗原(ABO)以及其他六个较小的贡献 基因位点，但未能识别出与VTE的高遗传性有关的其他变异。由于缺乏 全面了解静脉血栓栓塞症的遗传风险因素，目前的基因检测不能准确地 预测个人对VTE的易感性，并不能充分地为VTE的临床决策提供信息 预防和治疗。因此，迫切需要更完整的遗传风险数据来帮助临床医生 预测哪些人需要治疗以防止VTE的发生或复发。这项提议的目标是 识别新的、高影响VTE的遗传危险因素，并开始揭示其分子机制 受到新发现的风险变量的影响。这项提议的中心假设是，很大一部分人 VTE的未知遗传风险因素是聚集在有限数量的驱动风险的基因中的罕见变异 主要是由于功能丧失。这些尚未描述的变体有助于VTE的遗传性，但 GWAS无法检测到，因为它们单独太稀有了。为了确定改变静脉血栓形成风险的突变， 折叠稀有变异分析将使用之前收集的完整外显子组测序数据进行 VTE病例/对照研究。一位具有广泛特征的年轻健康人的后续靶向DNA测序 队列结合血浆抗原分析将揭示导致血栓前病变的分子机制。 携带VTE风险突变的个人的状态。新发现的VTE危险基因STAB2的功能研究 为了查明VTE案例中的数量或质量缺陷，将进行各种变化。附加功能 在通过邻近依赖鉴定生理稳定蛋白-2配体之后，将开发检测方法 生物素化和蛋白质组学。此外，为了全面表征错义突变对 稳定蛋白-2的功能，将进行稳定蛋白-2结构域的重点突变研究。成功后 完成拟议的研究，我们预计将发现以前未描述的基因缺陷 解释相当大比例的VTE遗传风险。我们还希望定义基本的机制 STAB2中的潜在遗传关联和其他新的遗传关联。执行这两项任务的能力 全基因组筛选和“湿实验室”实验是由申请人建立的交叉- 纪律协作。DNA测序和稀有变异分析在油井中的创新应用 特征化的人类队列，结合体外突变和蛋白质组学研究将导致新的 为预测、预防和治疗提供可重复的、临床有用的和个性化的信息的知识 以及静脉血栓栓塞症的治疗。

Project Abstract VTE affects 900,000 individuals in the US each year, and is highly heritable, with ~60% of lifetime risk attributable to genetic factors. To date only 50% of the genetic factors contributing to VTE have been described. Recently, genome-wide association studies (GWAS) of VTE have validated the contribution of common variants of coagulation factor V (F5) and common blood group antigens (ABO) as well as smaller contributions at six other gene loci, but have failed to identify additional variants implicated by the high heritability of VTE. Due to the lack of a comprehensive understanding of the genetic risk factors for VTE, current genetic testing cannot accurately predict an individual’s susceptibility for VTE and does not adequately inform clinical decision making for VTE prevention and treatment. Therefore, there is a critical need for more complete genetic risk data to help clinicians predict which individuals need treatment to prevent incident or recurrent VTE. The objective of this proposal is to identify new, high impact genetic risk factors for VTE and to begin to uncover the molecular mechanisms affected by newly identified risk variants. The central hypothesis of this proposal is that a large proportion of the unknown genetic risk factors for VTE are rare variants that cluster in a limited number of genes driving risk primarily through loss of function. These yet to be described variants contribute to the heritability of VTE but are undetectable by GWAS because they are individually too rare. To identify mutations that alter VTE risk, collapsing rare variant analyses will be performed with whole-exome sequencing data from a previously collected VTE case/control study. Subsequent targeted DNA sequencing in an extensively characterized young healthy cohort combined with plasma antigen assays will inform the molecular mechanisms leading to a prothrombotic state in individuals harboring VTE risk mutations. Functional studies of the newly identified VTE risk gene STAB2 to identify quantitative or qualitative deficiencies in the VTE case variants will be performed. Additional functional assays will be developed after identification of physiologic stabilin-2 ligands through proximity dependent biotinylation and proteomics. Furthermore, to comprehensively characterize the effect of missense mutations on stabilin-2 function, focused mutagenesis studies of stabillin-2 domains will be performed. Upon successful completion of the proposed research, we expect to have identified previously undescribed gene deficiencies that explain a substantial proportion of the inherited risk for VTE. We also expect to define the basic mechanisms underlying genetic associations in STAB2 and other novel genetic associations. The ability to execute both genome-wide screens and “wet lab” experimentation is facilitated by the applicant’s established cross- disciplinary collaborations. The innovative use of DNA sequencing and rare variant analyses in well characterized human cohorts, combined with in vitro mutagenesis and proteomic studies will lead to new knowledge that provides reproducible, clinically useful and personalized information for prognosis, prevention, and treatment of VTE.