Functional Dissection of CNVs in Neurodevelopmental Traits

了解拷贝数变异（CNVs）对人类病理学的贡献仍然具有挑战性， 部分原因是它们内部的基因座的复杂和多样的影响。在某些情况下，单一剂量敏感 轨迹驱动病理。在其他例子中，多个基因通过加性效应对表型做出贡献 通过复杂的基因相互作用。在上一个资助期，我们专注于缺失综合征， 和相互的CNVs，并询问我们是否可以开发工具来帮助识别驱动基因。 这项工作的进展为病理学的几个领域提供了信息。例如，将SIN 3B标识为 19p13.1上非复发性230 kb缺失的驱动因子，导致复杂的神经发育表型 增强了Sin 3/HDAC转录辅抑制因子复合物在神经发育中的作用， 对CNV表型复制的孟德尔突变的鉴定。对于17q24.2 CNV，我们了解到 关于合成CNV表型可能由BPTF和PSMD 12两者的剂量不平衡引起。最后， 与16p11.2 CNV相关的多种表型的建模显示了：（a）关键的神经发育 从人类、小鼠、大鼠到斑马鱼，颅面病理学是保守的;（B）证明 基因座之间的离散上位相互作用;以及（c）产生了一系列替代模式生物， 进行途径分析和药物发现。总的来说，CNV的遗传和功能解剖 Examples强调了三个观察结果：（a）CNV中并非所有基因都是剂量敏感的（怀疑， 但现在得到实验证据的支持）;（B）某些基因在一个方向上是剂量敏感的（增益， 损失，但不是两者）;和（c）非驱动基因可以参与不同的遗传相互作用。的知识和 获得的实验工具使我们有机会扩大我们的雄心。我们仍然不明白 CNV内组合剂量影响表型，以及从先前工作中获得的经验教训是否 可广泛推广的。此外，鉴于CNV对疾病负担的重要贡献，至关重要的是， 我们重视治疗途径的发展。我们提出三个目标：（1）我们将解剖一个 一组独特的CNV，其中表型仅由重复驱动以识别三倍体敏感基因， 询问疾病易感性是否由阈值效应驱动，以了解为什么只有 人类基因子集是剂量敏感的。(2)我们将利用现有的斑马鱼模型来描述 使用16p11.2的神经元和面部软骨表型的上位效应的分子特性 CNV，并询问我们是否可以在转录调控水平上检测上位性。(3)我们将联合收割机 使用连通性地图（CMap）Touchstone数据集的CNV驱动程序的斑马鱼模型的广泛库 以及新开发的安全性/有效性方案以鉴定候选治疗剂。我们的研究将 完善基因组疾病的遗传结构，告知遗传相互作用的分子基础， 为神经发育特征的治疗绘制了一条系统的道路。

Understanding the contribution of copy number variants (CNVs) to human pathology remains challenging, in part because of the complex and varied influence of loci within them. In some cases, a single dosage-sensitive locus drives pathology. In other examples, multiple genes contribute to phenotypes through additive effects and through complex genetic interactions. In the previous funding period, we focused on deletion syndromes and reciprocal CNVs and asked whether we could develop tools to aid the identification of driver genes. Progress in that work has informed several areas of pathology. For example, the identification of SIN3B as a driver of a non-recurrent 230 kb deletion on 19p13.1 that causes a complex neurodevelopmental phenotype reinforced the role of the Sin3/HDAC transcriptional corepressor complex in neurodevelopment and facilitated the identification of Mendelian mutations that phenocopy the CNV. In the case of the 17q24.2 CNV, we learned about the synthetic CNV phenotype likely caused by dosage imbalance of both BPTF and PSMD12. Finally, modeling of multiple phenotypes associated with the 16p11.2 CNV showed how: (a) key neurodevelopmental and craniofacial pathologies were conserved from humans, to mice, to rats, to zebrafish; (b) demonstrated discrete epistatic interactions between loci; and (c) generated a host of surrogate model organisms in which to perform both pathway analysis and drug discovery. Overall, the genetic and functional dissection of CNV exemplars has underscored three observations: (a) not all genes in a CNV are dosage sensitive (suspected, but now supported by experimental evidence); (b) some genes are dosage sensitive in one direction (gain, loss, but not both); and (c) non-driver genes can participate in distinct genetic interactions. The knowledge and experimental tools gained affords us the opportunity to expand our ambition. We still do not understand how intra-CNV combinatorial dosage influences phenotype, and whether the lessons learned from prior work are broadly generalizable. Moreover, given the non-trivial contribution of CNVs to disease burden, it is crucial that we pay attention to the development of therapeutic avenues. We propose three Aims: (1) We will dissect a unique set of CNVs, in which the phenotype is driven only by duplication to identify triplosensitive genes and ask whether disease susceptibility is driven by a threshold effect as a means to understanding why only a subset of human genes are dosage sensitive. (2) We will harness our existing zebrafish models to characterize the molecular properties of epistatic effects using the neuronal and facial cartilage phenotypes of the 16p11.2 CNV and ask whether we can detect epistasis at the level of transcriptional regulation. (3) We will combine our extensive repertoire of zebrafish models of CNV drivers with the Connectivity Map (CMap) Touchstone dataset and a newly developed safety/efficacy protocol to identify candidate therapeutics. Together, our studies will refine the genetic architecture of genomic disorders, inform the molecular basic of genetic interactions, and chart a systematic path toward therapeutics for neurodevelopmental traits.