Investigating Genomic Instability and Loss of the Y Chromosome in Alzheimer’s Disease

项目摘要 自90年代初以来，遗传因素已被证明在阿尔茨海默氏症的发病中起着重要作用 疾病（AD）风险。最近，Y染色体镶嵌丢失（LOY）已成为一种新的风险 AD的生物标志物，并通过我们自己的研究证实， AD诊断LOY是男性随着年龄增长而发生的躯体事件。虽然潜在的生物学 驱动这种风险的机制仍然未知，LOY结果的全基因组关联研究（GWAS） 确定了约156个基因座，其中包含参与细胞周期调控、有丝分裂途径和DNA损伤的基因 反应发现的基因组变异也预测了女性X染色体的丢失，这表明LOY是一种遗传性的基因。 在AD临床表型之前的男性中基因组不稳定性的标志物。典型AD病理学 包括淀粉样蛋白β和tau蛋白的异常产生和积累，这最终导致 斑块和神经原纤维缠结、神经元死亡和脑皮质体积损失。受两种基因的支持， 在分子生物学研究中，小胶质细胞对异常蛋白质的清除已经成为一种重要的疾病， 免疫系统功能现在被认为在AD中起关键作用。在这个项目中，我们将 探讨LOY与AD发病的关系。我们假设， 老年痴呆症，LOY在男性中是获得性基因组不稳定性的标志，通过增加AD的风险。 神经元或神经胶质衰老表型。我们将通过一个独特的融合， 群体水平分析和分子实验，以1）检查全血转录组学变化， LOY+个体;和2）使用诱导多能干细胞测定免疫细胞功能的差异 细胞系（iPSC）。

PROJECT SUMMARY Since the early 90's, genetic factors have been shown to play a formidable role in contributing to Alzheimer's Disease (AD) risk. More recently, mosaic loss of the Y chromosome (LOY) has emerged as a novel risk biomarker for AD, and was confirmed by our own study to confer between a 1.63 to 2 fold increased hazard for AD diagnosis. LOY is a somatic event that occurs in males as they age. While the underlying biological mechanism that drives this risk remains unknown, genome wide association studies (GWAS) of LOY outcomes identified ~156 loci that contain genes involved in cell cycle regulation, mitotic pathways, and DNA damage response. The discovered genomic variants also predict X chromosome loss in women, suggesting that LOY is a marker of genomic instability in males that precedes the AD clinical phenotype. Typical AD pathology includes the abnormal production and accumulation of amyloid beta and tau proteins, which ultimately leads to plaques and neurofibrilary tangles, neuronal death, and loss of brain cortical volume. Bolstered by both genetic and molecular studies, the clearance of abnormal proteins by microglia has emerged as an important disease mechanism; immune system function is now thought to play a critical role in AD. In this project, we will investigate the relationship between LOY and AD pathogenesis. We hypothesize that in the context of Alzheimer's Disease, LOY in males is a marker of acquired genomic instability increasing risk of AD through a neuronal or glial senescence phenotype. We will examine this hypothesis through a unique fusion of population-level analyses and molecular experiments to 1) examine whole-blood transcriptomic changes in LOY+ individuals; and 2) determine differences in immune cellular function using induced pluripotent stem cell lines (iPSCs) with LOY.