Genetic and Molecular Analysis of Congenital Heart Disease

描述(申请人提供)：先天性心脏病(CHD)，出生时存在的心脏畸形，是最常见的威胁生命的出生缺陷类别。房室间隔缺损(AVSD)是人类常见且严重的冠心病，占全部CHD的5%-10%，需要手术治疗的病例比例更高。从机制上了解房室间隔是改善结构性心脏病临床治疗方法的一个重要目标。R01的更新是基于对房室间隔的理解的范式转变。尽管房室间隔的经典观点是以心内膜垫为中心的心内事件为基础，但最近的研究表明，在心脏本身外的第二心场需要纤毛的Sonic Hedgehog(Shh)信号驱动房室间隔。在上一次授予期间，我们的实验室为这一范式转变做出了重大贡献，这两方面都意味着基于纤毛的信号(Kamp等人。2010年；Friedland-Little等人，2011年)和Hedgehog信令(Hoffmann等人，2009；Xie等人，2012年)。在这项建议中，我们利用对房室间隔的新理解来解决人类房室间隔的遗传病因，并更详细地研究房室间隔背后的发育机制。我们建议(1)对大量AVSD患者中的纤毛基因、Hedgehog信号组件和生心转录因子进行有针对性的测序；(2)分析AVSD中纤毛基因、Hedgehog信号组件和生心转录因子之间的相互作用；以及(3)询问形成房室间隔的心脏祖细胞中的Hedgehog分子网络。这项拟议工作的最终目的是了解房室间隔的遗传和分子基础。这一建议将增加对人类AVSD分子个体发育的理解。这项工作是确定人类CHD病因和改善CHD患者自然病史的重要一步。

DESCRIPTION (provided by applicant): Congenital Heart Disease (CHD), malformations of the heart present at birth, is the most common class of life-threatening birth defect. Atrioventricular Septal Defects (AVSDs) are a common and serious form of CHD in humans, comprising 5-10% of all CHD and a greater proportion of cases requiring surgical intervention. Gaining a mechanistic understanding of atrioventricular (AV) septation is an essential goal for improving clinical approaches to structural heart disease. This R01 renewal is based on a paradigm shift in the understanding of AV septation. Whereas the canonical view of AV septation was based on intracardiac events centered at the endocardial cushion, recent work demonstrated that cilia-required Sonic hedgehog (Shh) signaling in the Second Heart Field, outside of the heart proper, drives AV septation. During the last granting period, our laboratory significantly contributed towards this paradigm shift, both in the implication of cilia-based signaling (Kamp et al. 2010; Friedland- Little et al., 2011) and of Hedgehog signaling (Hoffmann et al, 2009; Xie et al, 2012). In this proposal, we harness a new understanding of AV septation to address the genetic etiology of AVSDs in humans and investigate the developmental mechanisms underlying AVSDs in more detail. We propose to (1) Perform targeted sequencing of the ciliome, Hedgehog signaling components, and cardiogenic transcription factors in a large cohort of AVSD patients; (2) analyze interactions between cilia genes, Hedgehog signaling components, and cardiogenic transcription factors in AVSDs; and (3) interrogate Hedgehog molecular networks in the cardiac progenitors that form the AV septum. The ultimate aim of the proposed work is to understand the genetic and molecular basis of AV septation. This proposal will increase understanding of the molecular ontogeny of human AVSDs. This work is an essential step towards defining the causes of human CHD and improving the natural history of patients with CHD.