A Gene-Network Discovery Approach to Structural Brain Disorders

项目摘要/摘要 无脑畸形是一种罕见的发育障碍，其特征是脑循环缺失或简化。没有 在现有治疗方法的情况下，它会导致发育迟缓、智力残疾和癫痫等严重的健康负担。而当 新一代DNA测序的出现为人类基因发现提供了前所未有的机遇 疾病，导致识别出一系列与无脑相关的基因，大约五分之一的患者 伴有无脑畸形的患者仍缺乏基因诊断。孟德尔病的基因发现受到基因座和 表型异质性，因此，系统级别的分析与机械特征的补充 候选变种是有保证的。在过去的15年里，我们已经确定并在功能上描述了多个 基因的中断与人类大脑皮层的畸形有关。我们建议利用病人- 用衍生干细胞和小鼠胚胎模型研究PIDDosome蛋白复合体在人类中的作用 大脑发育，并了解它的故障如何导致无脑。我们还建议进行基因- 负载和共表达分析为描述与无脑畸形有关的新基因和途径提供信息 通过在器官模型中。我们将使用患者和对照角质形成细胞来产生诱导多能干细胞。 以及2D和3D神经衍生品，以定义PIDD1突变的分子和细胞后果 通过在体小鼠建立神经发育过程中PIDD1丢失的模型。我们将进行基于基因网络的分析 120例无脑畸形患者的脑发育及基因和通路水平突变负荷分析 利用可用的全外显子组测序数据来识别和优先处理无脑畸形的新的致病基因。我们的多- 多面化方法有望揭示共同的分子途径和受影响的细胞类型，这些细胞在 人类胎儿神经发育导致遗传异质性背景下的无脑畸形 为人类疾病的大规模基因组研究中的变异优先顺序提供一个分析框架。

Project Summary/Abstract Lissencephaly is a rare developmental disorder characterized by absence or simplification of brain convolutions. With no available cure, it leads to significant health burden of developmental delay, intellectual disability, and seizures. While introduction of next-generation DNA sequencing offered unprecedented opportunities for gene discovery in human disorders, leading to the identification of an array of lissencephaly-associated genes, approximately a fifth of patients with lissencephaly still lack genetic diagnosis. Gene discovery in Mendelian disorders is hampered by locus and phenotypic heterogeneity and thus, a systems-level analysis complemented with mechanistic characterization of candidate variants is warranted. In the past decade and a half, we have identified and functionally characterized multiple genes whose disruption is associated with malformations of the human cerebral cortex. We propose to utilize patient- derived stem cell and embryonic mouse models to characterize the role of the PIDDosome protein complex in human brain development and understand how its malfunction can cause lissencephaly. We also propose to perform gene- burden and co-expression analyses to inform characterization of novel genes and pathways involved in lissencephaly through modeling in organoids. We will use patient and control keratinocytes to generate induced pluripotent stem cells and 2D and 3D neural derivatives to define the molecular and cellular consequences of PIDD1 mutations, accompanied by in vivo mouse models of PIDD1 loss during neurodevelopment. We will perform gene network-based analysis of human brain development and mutation burden analysis at the gene and pathway level of 120 lissencephaly patients with available whole-exome sequencing data to identify and prioritize novel causal genes for lissencephaly. Our multi- faceted approach is expected to reveal shared molecular pathways and affected cell types that are perturbed during human fetal neurodevelopment leading to the onset of lissencephaly in a genetically heterogenous background, also providing an analytical framework for variant prioritization in large-scale genomic investigation of human disorders.