Genetic Strategies for Neurodevelopmental Research

在美国，1-2%的儿童患有自闭症谱系障碍(ASD)。病原学和 自闭症的神经生物学基础尚不清楚，因此有针对性地进行有效的药物治疗。 是很罕见的。虽然已经创造了无数的遗传小鼠模型，其中许多表现出了一些表型 关于自闭症的特征，人们越来越担心啮齿动物模型可能不是创建 以认知和社交障碍为核心的儿童障碍的表现，如自闭症 功能。在过去5年中，通过使用CRISPR/CAS9等技术， 可应用于大型物种(如非人灵长类)的基因修饰生物的革命 (NHP)。这项应用的第一个目标是建立一个非人类的灵长类ASD的功能丧失模型 CHD8基因的修饰。编码染色质重构体CHD8的基因是 ASD患者中频繁突变的基因。CHD8自闭症的独特之处在于 具有渗透性，并具有行为和神经生物学表型。该基因功能丧失的个体 不仅患有自闭症，而且典型地表现为大头畸形/巨脑畸形。我们已经选择了这个基因作为 这是一个起点，因为加州大学戴维斯分校这一应用程序的联合调查人员一直在开发老鼠模型 与CHD8突变和巨脑畸形的分析是最近资助的自闭症中心的主要焦点 在心智研究所的卓越表现。该应用程序的第二个目标是在以下方面建立能力和专业知识 产生神经发育障碍的转基因非人类灵长类动物模型。我们认为 加州大学戴维斯分校及其加州国家灵长类动物研究中心拥有4000多只恒河猴， 老鼠生物学计划，在基因操作方面拥有专业知识，导致数百个具有临床意义的 小鼠模型，以及拥有神经发育障碍各方面专业知识的精神研究所 从遗传学到临床试验的研究，都处于非常有利的地位，能够产生和全面 评估这些动物模型。我们将成立一个领导小组，指导这一计划取得成功 开发有价值的神经发育障碍的非人类灵长类动物模型。对于这一初始阶段 研究我们建议1)实现非人灵长类的基因编辑策略，验证基因 编辑和高效生产胚胎以供以后植入2)以生产最多10只活恒河猴 CHD8功能缺失突变3)确定正常和异常的结构和运动轨迹 CHD8功能突变缺失恒河猴脑功能发育的研究 转基因后代的行为分析。虽然此应用程序的近期目标是 开发有价值的NHP模型，以促进理解自闭症的神经生物学基础，a 长期目标是建立基础设施，使转基因猴子的产生能够 更全球化的翻译生物医学研究--我们认为这符合国家利益。

Autism Spectrum Disorder (ASD) affects 1-2% of children in the United States. The etiology(ies) and neurobiological underpinnings of autism remains unclear and hence targets for effective medical treatments are rare. While myriad genetic mouse models have been created, and many demonstrate some phenotypic features of autism, there is growing concern that rodent models may not be the best approach for creating phenocopies of childhood disorders, such as autism, that have cognitive and social disabilities as their core features. Over the last 5 years, through the use of techniques such as CRISPR/Cas9, there has been a revolution in genetically modifying organisms that can be applied to large species such as nonhuman primates (NHP). A first goal of this application is to develop a nonhuman primate model of ASD through loss of function modifications to the CHD8 gene. The gene encoding the chromatin remodeler CHD8 is among the most frequently mutated genes in individuals with ASD. The CHD8 form of autism is unique in being both highly penetrant and having a behavioral and neurobiological phenotype. Individuals with loss of function of this gene not only have autism but typically demonstrate macrocephaly/megalencephaly. We have selected this gene as a starting point because UC Davis Co-investigators on this application have been developing mouse models with Chd8 mutations and analysis of megalencephaly is a major focus of a recently funded Autism Center of Excellence at the MIND Institute. A second goal of the application is to build capacity and expertise in generating genetically modified nonhuman primate models of neurodevelopmental disorders. We argue that UC Davis, with its California National Primate Research Center that houses over 4000 rhesus monkeys, the Mouse Biology Program that has expertise in genetic manipulations leading to hundreds of clinically significant mouse models, and the MIND Institute which houses expertise on all facets of neurodevelopmental disorders research from genetics to clinical trials, is extraordinarily well-positioned to generate and comprehensively evaluate these animal models. We will establish a Leadership Group that will guide this program to successful development of valuable nonhuman primate models of neurodevelopmental disorders. For this initial phase of studies we propose 1) to implement strategies for gene editing of the nonhuman primate, validation of gene editing and efficient production of embryos for later implantation 2) to produce up to ten live rhesus monkeys with Chd8 loss of function mutations 3) to determine normal and abnormal trajectories of structural and functional brain development for rhesus monkeys with Chd8 loss of function mutations and 4) to carry out behavioral analyses of the genetically modified offspring. While the proximal goal of this application is to develop a valuable NHP model to facilitate understanding of the neurobiological underpinnings of autism, a long-term goal is to establish infrastructure to enable the generation of genetically modified monkeys for translational biomedical research more globally - which we believe to be in the national interest.