Clinical genetics of drug-resistant epilepsy with focal cortical dysplasia

项目摘要（最多30行;目前为27行） 大约三分之一的癫痫患者对目前可用的药物治疗方案没有反应，尽管许多人 耐药性局灶性癫痫适合手术治疗。在最常见的癫痫相关 结构性脑损伤是局灶性皮质发育不良（FCD）。FCD是皮质发育的畸形 其中受影响的神经元在子宫内不能迁移到适当的新皮层形成中。体细胞变异体 据报道，10-20个基因是FCD亚组的根本原因1 -13。然而，我们和其他人 已经表明，60-90%的FCD I型（FCD I）和FCD II型（FCD II）患者缺乏任何遗传性 使用现有的测试方法时出现异常。更令人吃惊的是，只有一个基因 在FCD I12中识别。一个原因可能是以前所有关于FCD的遗传学研究都是观察性的 在候选基因中进行了研究，没有针对对照的罕见变异负荷测试， 小（n<77）、特征不明确的群组。这些研究都没有研究拷贝数变异或 体细胞水平的染色体改变。此外，尚未探索FCD样品中的RNA失调 呢在这里，我们提出了迄今为止最全面的FCD I和II的独特队列的遗传分析。 前所未有的深度临床表型。我们的队列比以前任何队列都大13倍以上 发表的FCD I和II队列。与对照组相结合，该队列首次进行了罕见变异负荷分析 用于FCD以确认提出的并发现新的FCD相关基因。此外，我们是第一个 从FCD患者的脑组织中生成单核RNA测序数据，以研究转录组- 与FCD I和II以及遗传亚型相关的水平改变。项目假设：我们的综合 一种新的方法，使用了来自患有糖尿病的患者的特征良好的脑组织和配对的血液样本， FCD I或FCD II引起的癫痫将鉴定新的FCD致病基因和变体， 治疗意义影响：更好地了解FCD病因的遗传基础将导致 引入新的基于基因的诊断策略和靶向药物，以全面管理患者的癫痫发作 同时避免了通常与当前治疗干预相关的一系列副作用。目标1： 鉴定FCD I和FCD II的新致病基因以及生殖系和体细胞脑变异负荷。目标二： 识别疾病相关的体细胞拷贝数变异（CNVs）和杂合性缺失（CN-LOH） 与FCD I和FCD II相关的结构变体。目的3：对切除的脑组织进行单个核团的分析 RNA-seq（snRNA-seq）用于鉴定与FCD相关的细胞类型特异性转录改变 组织病理学和特定突变。

Project Summary (30 lines max; currently at 27 lines) About one-third of people with epilepsy do not respond to currently available drug regimens, though many have drug-resistant focal epilepsy amenable to surgical treatment. Among the most common epilepsy-associated structural brain lesions are Focal Cortical Dysplasias (FCDs). FCDs are malformations of cortical development where the affected neurons fail to migrate in the proper neocortex formation in utero. Somatic variants in about 10-20 genes have been reported as the underlying cause for a subset of FCDs1–13. However, we and others have shown that 60-90% of patients with FCD type I (FCD I) and FCD type II (FCD II) lack any genetic abnormality when using currently available testing methods. More strikingly, only a single gene has been identified in FCD I12 to date. One reason could be that all previous genetic studies in FCD were observational studies in candidate genes without rare variant burden testing against controls and have been performed in small (n<77), poorly characterized, cohorts. None of these studies investigated copy number variants or chromosomal alterations at the somatic level. Also, RNA dysregulation in FCD samples has not been explored yet. Here, we propose the most comprehensive genetic analysis to date of a unique cohort of FCD I and II patients with unprecedented deep clinical phenotyping. Our cohort is >13 times larger than any previously published FCD I and II cohort. Combined with controls, this cohort enables the first rare variant burden analysis for FCDs to confirm proposed and discover novel FCD-associated genes. In addition, we are the first to generate single-nucleus RNA sequencing data from the brain tissue of FCD patients to study transcriptome- level alterations associated with FCD I and II and genetic subtypes. Project hypothesis: Our comprehensive and novel approach using well-characterized brain tissues and paired blood samples from patients with epilepsy due to FCD I or FCD II will identify novel FCD causal genes and variants with clear diagnostic and therapeutic implications. Impact: A better understanding of the genetic basis of FCD etiology will lead to the introduction of novel gene-based diagnostic strategies and targeted drugs to fully manage a patient's seizures while avoiding the spectrum of side effects typically associated with current therapeutic interventions. AIM 1: Identify novel causal genes for FCD I and FCD II with germline and somatic brain variant burden. Aim 2: Identify disease-associated somatic copy number variants (CNVs) and loss-of-heterozygosity (CN-LOH) structural variants associated with FCD I and FCD II. Aim 3: Analyze resected brain tissues by single-nucleus RNA-seq (snRNA-seq) to identify cell type-specific transcriptional alterations associated with FCD histopathologies and with specific mutations.