Inherited aortic disease: identification of novel disease genes and functional analysis of the molecular pathogenesis

在西方国家，胸主动脉瘤和夹层（TAAD）约占死亡率的1%。TAAD可能以孤立的非综合征形式出现，也可能与其他临床特征（如马凡氏综合征或Loeys-Dietz综合征）合并出现。TAAD有很强的遗传易感性。个体化风险评估、预防措施的应用以及适当的治疗和护理概念在很大程度上取决于对潜在疾病的正确诊断。结合临床和分子遗传信息对正确诊断至关重要。只有大约一半的患者在已知的疾病基因中表现出致病性突变，因此进一步的异质性是明显的。该项目的中心目标是确定TAAD的其他疾病基因。我们将对10名TAAD患者进行全外显子组测序（WES），并随后进行多外显子组比较，从而通过遗传（而非功能）方法产生新的候选基因。我们将在180例突变阴性TAAD谱系障碍患者中通过基因面板测序验证新的候选基因和已经发现的候选基因（初步工作）。这一概念使我们能够更深入地了解（许多患者）许多候选基因的表型特性。通过各种分子生物学，生物化学和细胞生物学方法，我们将分析新的taad相关突变的病理生理后果。这对于确认罕见序列变异的致病性至关重要。此外，更好地了解TAAD的分子发病机制可能有助于开发基于科学的治疗方案。在我们的初步工作中，对一个受影响家庭的亲属进行WES鉴定，发现CDKL1是一个新的TAAD候选基因。我们通过在第二个家庭的两个受影响的兄弟姐妹中发现另一个CDKL1序列改变来证实CDKL1是一种疾病基因。因此，我们将立即开始对假定的致病性CDKL1蛋白变异进行功能分析。渐渐地，我们将包括尚未发现和有待证实的致病序列变化在我们的功能分析。这些研究将适用于各自种类的蛋白质。我们的最终目标是为TAAD谱系障碍患者提供充分的病因学基础护理，我们提出的项目涵盖了现代人类基因研究的整个范围，包括临床详细特征患者的全外显子组和基因面板测序，以及致病突变的功能表征。

Thoracic aortic aneurysms and dissections (TAAD) account for about 1% of mortality in western countries. TAAD may occur as isolated nonsyndromic form or in conjunction with other clinical features such as in patients with Marfan or Loeys-Dietz syndrome. There is a strong genetic predisposition to TAAD. Individualized risk assessment, application of preventive measures and adequate therapy and aftercare concepts strongly depend on proper diagnosis of the underlying disease. Combined clinical and molecular genetic information is crucial for correct diagnosis. Only about half of the patients show pathogenic mutations in known disease genes, thus further heterogeneity is evident. The central goal of the project is to identify additional disease genes for TAAD. We will perform whole exome sequencing (WES) in 10 patients with TAAD and subsequent multiple exome comparison, thereby generating novel candidate genes by a genetic (but not functional) approach. We will verify novel candidate genes and already uncovered candidate genes (preliminary work) by gene panel sequencing in our cohort of 180 mutation negative patients with TAAD spectrum disorders. This concept enables a deeper view (many patients) in the phenocritical properties of a number of candidate genes. By using various molecular biological, biochemical and cell biological methods, we will analyze the pathophysiological consequences of the novel TAAD-associated mutations. This is essential in order to confirm the pathogenicity of rare sequence variants. Moreover, a better understanding of the molecular pathogenesis of TAAD may enable developing scientifically based treatment options. In our preliminary work, WES of relatives in an affected family identified CDKL1 as a novel TAAD candidate gene. We verified CDKL1 as a disease gene by uncovering another CDKL1 sequence alteration in two affected sibs in a second family. Therefore, we will start immediately with functional assays for the putative pathogenic CDKL1 protein variants. Gradually, we will include yet to be discovered and to be verified pathogenic sequence changes in our functional analyses. These studies will be adapted to the respective classes of proteins. With the ultimate goal to provide an adequate etiology-based care for patients with TAAD spectrum disorders, our proposed project covers the entire spectrum of modern human genetic research including whole exome and gene panel sequencing in clinically detailed characterized patients as well as functional characterization of pathogenic mutations.