Project 2: Therapeutic Gene Editing for Friedreich's Ataxia

项目摘要项目2(FRDA) Friedreich共济失调(FRDA)是一种常染色体隐性遗传病，以进行性共济失调和损害为特征 对神经系统来说，这通常与肌肉无力、痉挛、心肌病和糖尿病有关 糖尿病。FRDA是由Frataxin(FXN)蛋白水平不足引起的，FXN通常由GAA三联体引起 FXN基因内含子1的重复扩张导致转录抑制。FXN GaA-的长度 在普通人群中重复出现的频率在5-60之间，而FRDA患者的重复频率可能在66-1200以上 重复，通常有600到900个重复。在某些体细胞中，长GAA重复序列经历进行性不稳定 主要导致重复扩增，从而导致FXN蛋白丢失的细胞类型。这些组织可以 受累于FRDA的包括背根神经节(DRGs)、心脏和胰腺。疾病的发作 In与最短的FXN等位基因的长度呈反相关，通常出现在10-15岁 年龄，尽管大约25%的患者有不典型的表现，起病较晚。 虽然有些症状可以通过物理治疗和手术来改善，但没有有效的治愈或治疗方法 对于更广泛的FRDA表型尚未获得批准。患有FRDA的患者的预期寿命通常是 40-50岁。 在这个FLOGER项目中，我们的目标是改善FXN蛋白的表达，从而能够阻止疾病的进展 FRDA患者。具体来说，我们的目标是：(1)优化基因组编辑策略以纠正FRDA重复 扩大；(2)优化基因组编辑策略以纠正小鼠的FRDA重复扩大；以及(3)执行 临床前IND使研究能够评估SAFET和有效性。我们将与基因编辑核心密切合作 在FRDA模型系统中开发最新的基本编辑和/或主要编辑技术。我们将使用以下内容迭代 基因编辑核心，确保我们的基因组编辑工具最大化目标编辑效率，最大限度地减少 不受欢迎的基因编辑副产品和脱靶编辑事件，并最大限度地与体内兼容 具有潜在治疗意义的给药方法。

PROJECT SUMMARY PROJECT 2 (FRDA) Friedreich's Ataxia (FRDA) is an autosomal recessive disorder characterized by progressive ataxia and damage to the nervous system, that is often associated with muscle weakness, spasticity, cardiomyopathy and diabetes mellitus. FRDA is caused by a deficiency in frataxin (FXN) protein levels that usually arises from a GAA-triplet repeat expansion in intron 1 of the FXN gene which results in transcriptional repression. The length of FXN GAA- repeats in the general population ranges from ~5-60, while FRDA patients may present with 66 to well over 1200 repeats, typically 600 to 900 repeats long. Long GAA-repeats undergo progressive instability in some somatic cell types that predominantly results in repeat expansion and consequently loss of FXN protein. The tissues that are affected in FRDA include the dorsal root ganglia (DRGs), the heart, and the pancreas. The onset of disease in patients is anticorrelated with the length of the shortest FXN allele, which typically presents at 10-15 years of age, though approximately 25% of patients have an atypical presentation with later disease onset. Although some symptoms can be ameliorated by physical therapy and surgery, no effective cure or treatment for the broader FRDA phenotype has yet been approved. The life expectancy for patients with FRDA is typically 40-50 years of age. In this follower project, we aim to improve FXN protein expression to enable rescue of disease progression in FRDA patients. Specifically, we aim to: (1) Optimize genome editing strategies to correct FRDA repeat expansion; (2) optimize genome editing strategies to correct FRDA repeat expansion in mice; and (3) perform pre-clincial IND enabling studies to assess safet and efficacy. We will work closely with the Gene Editing Core to develop the latest base editing and/or prime editing technologies in FRDA model systems. We will iterate with the Gene Editing Core to ensure that our genome editing tools maximize on-target editing efficiencies, minimize undesirable gene editing byproducts and off-target editing events, and maximize compatibility with in vivo delivery methods of potential therapeutic relevance.