Cellular consequences and convergent biology of schizophrenia-associated rare variants in the diverse GPC cohort

项目摘要/摘要 最近的发现涉及到特定的基因变异，这些变异赋予精神分裂症(SZ)极高的风险， 毁灭性的精神综合症。除了这些基因发现之外，还有一些类似的进展 分子神经科学，包括诱导多能干细胞技术；高通量细胞 高含量成像和单细胞基因组学等技术；以及多重“细胞村”方法。 这些技术允许对以前的复杂生物过程进行严格而有效的询问 难以接近的人类神经细胞类型。基因发现和技术进步的结合是 解决现代精神病学中的“大白鲸”问题的有力工具：什么是 导致SZ表型的潜在病理生理学？我们认为稀有SZ的高外显率 突变源于分子和细胞层面的巨大影响。我们将确定下游目标并 5种罕见的大效应SZ相关变异对通路的影响：染色体缺失 位置2p16(定位于NRXN1基因)，3q29，15q13.3，22q11.2，16p11重复。一个关键的优势 这项建议的一部分是我们进入基因组精神病学队列(GPC)。重要的是，GPC是一个多样化的群体 具有显著的非洲血统。我们将选择之前储存的冷冻保存的材料进行研究 来自携带这五种已定义变种之一的SZ患者的淋巴细胞(n=20，每种基因型)， 优先考虑代表性不足的少数群体，以产生iPS细胞系。GPC的一个明显优势是它的大 不同的对照样本，允许我们选择与SZ基因组背景匹配的对照(n=40) 案例，增加了我们研究的严谨性。关于这些与SZ相关的稀有物种的一致但令人惊讶的观察 变种是它们在效应大小和表型特征上的相似性，从而产生了这样的假设 这些变异体聚集在下游的分子靶点和/或细胞通路上。我们将检验这一假设 SZ相关的罕见突变在染色质水平上引起神经元的分子扰动 可及性和基因表达以及受两个或更多这些SZ相关基因或途径影响 变异体相互汇聚，重叠部分比预期的要多。最后，我们将验证分子途径 采用多模式细胞表型水平分析。确定特定的生物过程，这些过程 SZ相关基因座的干扰将为了解这种疾病的复杂分子生物学打开一扇窗。这个 我们机械学研究的基础将包括具有不同遗传背景的受试者 历史上在基因研究中的代表性不足，确保我们的结果可以推广到这些社区， 他们不成比例地遭受不利的精神健康后果。此处生成的工具和数据将 支持精神健康领域与NIMH优先事项保持一致，带来对神经生物学的变革性见解 并发现可能成为治疗发现起点的新靶点。

Project Summary / Abstract Recent discoveries implicate specific genetic variants that confer extremely high risk for schizophrenia (SZ), a devastating psychiatric syndrome. Alongside these genetic discoveries there have been parallel advances in molecular neuroscience, including induced pluripotent stem (iPS) cell technology; high-throughput cellular technologies such as high content imaging and single cell genomics; and multiplex “cell village” approaches. These techniques allow for rigorous yet efficient interrogation of complex biological processes in previously inaccessible human neuronal cell types. The combination of genetic findings and technological advances are powerful tools for addressing what has become the “great white whale” of modern psychiatry: What is the underlying pathophysiology that gives rise to a SZ phenotype? We propose that high penetrance of rare SZ mutations derive from large effects at the molecular and cellular levels. We will identify downstream targets and pathways impacted by five rare SZ-associated variants with large effect sizes: deletions at chromosomal locations 2p16 (localized to the NRXN1 gene), 3q29, 15q13.3, 22q11.2, and duplication at 16p11. A key strength of this proposal is our access to the Genomic Psychiatry Cohort (GPC). Importantly, the GPC is a diverse cohort with significant representation of African ancestry. We will select for study previously-banked cryopreserved lymphocytes from individuals with SZ who carry one of these five defined variants (n=20 each genotype), prioritizing underrepresented minorities, to generate iPS cell lines. A clear advantage of the GPC is its large diverse control sample, allowing us to select controls (n=40) that are matched by genomic background to the SZ cases, increasing the rigor of our study. A consistent but surprising observation about these SZ-associated rare variants is their similarity in both effect size and phenotypic characteristics, giving rise to the hypothesis that these variants converge on downstream molecular targets and/or cellular pathways. We will test the hypothesis that SZ-associated rare mutations cause molecular perturbations in neurons at the level of chromatin accessibility and gene expression and that genes or pathways impacted by two or more of these SZ-associated variants converge, with more overlap than expected by chance. Finally, we will validate molecular pathways using multimodal cellular phenotypic levels of analysis. Identifying the specific biological processes that are disrupted by SZ-associated loci will open a window into the complex molecular biology of this disorder. The substrate for our mechanistic studies will include subjects with diverse genetic backgrounds that have been historically underrepresented in genetic studies, ensuring that our results are generalizable to these communities, who suffer disproportionately from adverse mental health outcomes. The tools and data generated herein will support the mental health field aligning with NIMH priorities, lead to transformative insights into the neurobiology of SZ, and uncover novel targets that may be a launch point for therapeutic discovery.