SINGLE SUTURE CRANIOSYNOSTOSIS: CANDIDATE GENE AND PATHWAY DISCOVERY

描述（由申请人提供）：颅缝闭合是颅骨的病理性融合。在过去的十年中，我们对涉及颅缝闭合的多种畸形综合征的理解取得了重大进展。研究表明，成纤维细胞生长因子受体（FGFR1-3）、TWIST1、MSX2和EFNB1的突变都会导致人类颅缝闭锁综合征。在几个国际实验室开展的这项广泛的工作，对我们如何诊断和建议患有综合征性颅缝闭塞的家庭产生了重大影响。尽管关于综合征形式的知识迅速增长，但孤立性结膜紧闭的原因仍然难以捉摸。虽然远比综合征形式更常见，相对较少的研究集中在孤立性颅缝闭锁的分子发病机制。这组颅骨畸形的频率，复杂的外科治疗的需要及其相关的发病率使得孤立性颅缝闭闭成为一个需要加强科学研究的候选者。我们建议使用三种方法来识别和表征孤立颅缝闭锁的候选遗传原因：高通量基因组测序，大规模微阵列表达分析和发育基因表达。我们利用从正常颅骨发育和颅缝闭锁综合征形式的调查中获得的知识，提出了两个相互关联的假设：(A)两类基因的罕见序列变异导致孤立性颅缝闭锁：那些调节缝线发育的基因和那些突变时导致综合征性颅缝闭锁的基因；(B)参与颅骨缝合发育的遗传通路和那些在综合征性颅缝闭中受到影响的遗传通路在孤立的、非综合征性颅缝闭中也同样受到影响。在这个建议中，我们描述了一系列的实验，旨在通过鉴定罕见的遗传变异，改变颅骨成骨细胞基因表达，以及候选基因的时间和空间表达来发现孤立性颅缝闭锁的潜在分子原因。我们研究团队的专业知识和互补的高通量方法的可用性使得对孤立性颅缝闭闭的遗传和发育发病机制的全面研究得以发展。

DESCRIPTION (provided by applicant): Craniosynostosis is the pathologic fusion of the calvaria. Over the past ten years significant advances have been made in our understanding of multiple malformation syndromes that involve craniosynostosis. It has been shown that mutations in the fibroblast growth factor receptors (FGFR1-3), TWIST1, MSX2, and the EFNB1 each cause craniosynostosis syndrome in humans. This extensive body of work, carried out in several international laboratories, has significantly impacted how we diagnose and counsel families with syndromic craniosynostosis. Despite the rapid growth of knowledge regarding syndromic forms, the causes of isolated synostosis remain elusive. Though vastly more common than syndromic forms, relatively little research has focused on the molecular pathogenesis of isolated craniosynostosis. The frequency of this group of calvarial malformations, the need for complex surgical management and its associated morbidity make isolated craniosynostosis a candidate for intense scientific investigation. We propose the use of three approaches to identify and characterize candidate genetic causes of isolated craniosynostosis: high throughput genomic sequencing, large-scale microarray expression analysis, and developmental gene expression. We have used knowledge gained from the investigation of normal calvarial development and syndromic forms of craniosynostosis to develop two interrelated hypotheses: (A) Rare sequence variants in two classes of genes result in isolated craniosynostosis: those that regulate suture development and those that, when mutated, cause syndromic craniosynostosis; and (B) Genetic pathways involved in cranial suture development and those impacted in the syndromic craniosynostoses are similarly affected in isolated, non-syndromic craniosynostosis. In this proposal, we describe a series of experiments designed to discover potential molecular causes of isolated craniosynostosis through the identification of rare genetic variants, altered calvarial osteoblast gene expression, and the temporal and spatial expression of candidate genes. The expertise of our research team and the availability of complementary high throughput approaches has allowed for the development of a comprehensive investigation of the genetic and developmental pathogenesis of isolated craniosynostosis.