Genetic Factors Governing Inter-individual Variation to Oxidative Stress Response

描述（由申请人提供）：我建议测量个体和人群中氧化应激反应的变化，并确定与这种变化相关的遗传基因座。氧化应激与年龄相关疾病的病因学密切相关，并作为长寿的决定因素。介导氧化应激反应的途径已被广泛研究，但我们对这些途径功能的个体差异仍知之甚少。了解个体间氧化应激反应变化的因素可能会提高我们对年龄相关疾病和生理衰退的理解。在这里，我提出了一系列的实验和统计分析，以研究氧化应激反应的变化的遗传基础。具体来说，在目标1中，我将从70名高加索人和70名非洲裔美国人中纯化CD 4 + T细胞。我将这些细胞暴露于氧化应激72小时，通过培养他们在升高（20%）的氧气水平，同时保持控制细胞从相同的个人在生理（5%）氧气水平。在此期间的特定时间点，我将测量氧化型谷胱甘肽与还原型谷胱甘肽（氧化应激的指标）的比率;氧化型鸟嘌呤与未修饰的鸟嘌呤的比率。 鸟嘌呤（氧化应激诱导的DNA损伤的指标）;和全基因组mRNA丰度，在处理和对照细胞。在目标2中，我将收集目标1中使用的所有样品的基因型，并绘制解释氧化应激反应变化的数量性状位点（QTL），包括表达QTL。然后将在目标3中使用报告基因测定来验证大约30个推定的eQTL。

DESCRIPTION (provided by applicant): I propose to measure variation in oxidative stress response across individuals and populations, and to identify the genetic loci that are associated with such variation. Oxidative stress has been strongly implicated in the etiology of age-related disease and as a determinant of longevity. Pathways that mediate oxidative stress response have been extensively studied, but we still know relatively little about individual variation in th function of these pathways. Understanding the factors that govern variation in oxidative stress response across individuals may improve our understanding of age-related disease and physiological decline. Here, I propose a series of experiments and statistical analyses to study the genetic basis of variation in oxidative stress response. Specifically, in Aim 1, I will purify CD4+ T cells from 70 Caucasians and 70 African Americans. I will expose these cells to oxidative stress for 72 hours by culturing them in elevated (20%) oxygen levels, while maintaining control cells from the same individuals in physiological (5%) oxygen levels. At specified time points during this period, I will measure the ratio of oxidized glutathione to reduced glutathione (an indicator of oxidative stress); the ratio of oxidized guanine to unmodified guanine (an indicator of oxidative stress-induced DNA damage); and genome-wide mRNA abundance, in both treated and control cells. In Aim 2, I will collect genotypes from all samples used in aim 1 and map quantitative trait loci (QTLs), including expression QTLs, that explain variation in oxidative stress response. Reporter gene assays will then be used in Aim 3 to validate approximately 30 of the putative eQTLs.