Clinical genetics of drug-resistant epilepsy with focal cortical dysplasia

项目摘要(最多30行；当前为27行) 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，尽管许多人对此有反应 耐药性局灶性癫痫可手术治疗。与癫痫有关的最常见的 脑部结构性病变为局灶性皮质发育不良(FCDs)。FCDs是皮质发育的畸形 在子宫中，受影响的神经元不能在适当的新皮质形成中迁移。体细胞变异在大约 据报道，10-20个基因是导致FCDs1-13亚群的潜在原因。然而，我们和其他人 研究表明，60%-90%的FCD I型(FCD I)和FCD II(FCD II)患者缺乏任何基因 使用当前可用的测试方法时出现异常。更引人注目的是，只有一个基因 到目前为止在FCD i12中识别的。其中一个原因可能是FCD之前的所有遗传学研究都是观察性的。 在没有对照的罕见变异负荷测试的候选基因中的研究已经在 小(n&lt；77)，特征不佳，队列。这些研究中没有一项是研究拷贝数变异或 体细胞水平的染色体改变。此外，FCD样本中的RNA失调还没有被研究过 现在还不行。在这里，我们提出了迄今为止对FCD I和II独特队列的最全面的基因分析 患者具有前所未有的深度临床表型。我们的队伍比以前的任何人都大13倍 发表了FCD I和II队列。与对照相结合，这一队列实现了第一次罕见的变化负担分析 以供FCDs确认和发现新的FCD相关基因。此外，我们是第一个 从FCD患者脑组织中产生单核RNA测序数据以研究转录组- 与FCD I和II及遗传亚型相关的水平改变。项目假设：我们的综合 和新的方法使用特征良好的脑组织和来自患者的配对血液样本 由FCD I或FCD II引起的癫痫将识别新的FCD致病基因和变异，具有明确的诊断和 治疗方面的影响。影响：对FCD病因的遗传学基础的更好理解将导致 引入新的基于基因的诊断策略和靶向药物来完全控制患者的癫痫发作 同时避免了与当前治疗干预措施相关的典型副作用。目标1： 发现具有胚系和体细胞脑变异负荷的FCD I和FCD II的新的致病基因。目标2： 识别疾病相关的体细胞拷贝数变异(CNV)和杂合性缺失(CN-LOH) 与FCD I和FCD II相关的结构变异：目标3：对切除的脑组织进行单核分析 RNA-seq(SnRNA-seq)用于识别与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.