NOVEL APPROACHES TO INVESTIGATE GENETIC CORRELATES OF SMOKING BEHAVIORS

研究吸烟行为遗传相关性的新方法

• 批准号: 9246511
• 负责人: ADAM JOSEPH BLOOM
• 金额: $ 14.11万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-01 至 2019-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9246511
• 关键词: 19q13; 5' Untranslated Regions; Affect; Alleles; American; Area; Behavioral; Biological; Biology; Brain; CYP2B6 gene; Candidate Disease Gene; Carbon Monoxide; Cations; Cell Culture Techniques; Cell Hypoxia; Cessation of life; Cigarette; Complex; Consumption; Cultured Cells; Data; Disease; Drug abuse; Enzymes; Exhalation; Exons; Extrahepatic; FMO3; Family; Gene Expression; Genes; Genetic; Genetic Models; Genetic Polymorphism; Genetic Transcription; Genetic study; Genotype; Glucuronides; Goals; Grant; Hepatic; Heritability; Human; Human Genetics; Hypoxia; Hypoxia Inducible Factor; In Vitro; Intervention; Lead; Liver; Measurement; Measures; Mentors; Messenger RNA; Metabolic; Metabolism; Methods; Modeling; Nicotine; Nicotine Dependence; Oral; Pathway interactions; Pharmacology; Pharmacotherapy; Phenotype; Process; Procollagen-Proline Dioxygenase; Public Health; RNA Splicing; Sampling; Smoker; Smoking; Smoking Behavior; Substance abuse problem; Testing; Tissue Sample; Tissues; Training; Variant; Withholding Treatment; Work; Wound Healing; addiction; base; career; cigarette smoking; disorder risk; experimental study; gene function; genetic association; genetic predictors; genome wide association study; genome-wide; human tissue; improved; in vivo; mRNA Expression; novel; novel strategies; oxidation; personalized medicine; protein expression; public health relevance; response; smoking cessation; stroke recovery; success; trait; tumor growth

DESCRIPTION (provided by applicant): Disease associated with cigarette smoking remains the largest cause of preventable death. A large margin for improvement in smoking cessation treatment exists, with great potential to benefit public health: more than half of American smokers attempt to quit every year, but only ~6% succeed annually. Differences in smoking phenotypes, including cessation, have significant genetic components, but the large majority of this influence is unexplained. Genetic studies of smoking behavior that reveal the mechanisms underlying variation in these traits will identify further targets for pharmacotherapy and aid in improving personalized cessation treatment. Utilizing measurements from an in vivo nicotine metabolism experiment, I developed a predictive genetic model that explains >70% of the variation in oral nicotine C-oxidation (the primary nicotine metabolism pathway), based on CYP2A6 genotype. Model predictions were significantly associated with different measures of cigarette consumption and smoking cessation success in further subjects. The model also allowed me to demonstrate two key novel findings: the independent influences upon smoking behaviors of polymorphisms in 1) EGLN2, a.k.a. Hypoxia Inducible Factor Prolyl Hydroxylase, which initiates a transcriptional cascade in response to cellular hypoxia, and 2) in FMO3 and CYP2B6, further nicotine metabolism genes that may have important extra-hepatic activity. The specific aims of this grant are: 1) Develop a comprehensive predictive genetic model of nicotine metabolism incorporating all three nicotine metabolism pathways and their associated genes, focusing on CYP2A6, the UGTs and FMOs. The improved model will then be applied in further samples to determine the influence of heritable differences in nicotine metabolism upon smoking phenotypes; 2) Identify variants that alter nicotine metabolism gene function and demonstrate the mechanisms of their effects. I will focus especially on protein and mRNA expression, and splicing, in human brain and liver samples; 3) Identify variants in EGLN2 and other hypoxia-response candidate genes, and determine the mechanisms of their effects on smoking phenotypes. My preliminary data indicate an EGLN2 variant associated with nicotine dependence and cigarette consumption alters the relative expression of different EGLN2 5'UTR mRNA splice-variants. I will identify differences in gene and protein expression influenced by EGLN2 genotype in cells cultured under normal and hypoxic conditions. The goal of this K01 application is to obtain further training in statistical human genetics and cell culture under special conditions and to apply this expertise to problems of substance abuse.

描述（由申请人提供）：与吸烟有关的疾病仍然是可预防死亡的最大原因。戒烟治疗有很大的改进空间，对公共卫生有很大的好处：每年有一半以上的美国吸烟者试图戒烟，但每年只有6%的人成功。吸烟表型的差异，包括戒烟，有重要的遗传成分，但这种影响的大部分是无法解释的。吸烟行为的遗传研究揭示了这些特征变异的潜在机制，将进一步确定药物治疗的目标，并有助于改善个性化的戒烟治疗。利用体内尼古丁代谢实验的测量结果，我建立了一个预测遗传模型，该模型解释了基于CYP2A6基因型的口服尼古丁c -氧化（主要尼古丁代谢途径）的70%的变异。模型预测与其他受试者的香烟消费和戒烟成功的不同措施显著相关。该模型还让我证明了两个关键的新发现：1)EGLN2多态性对吸烟行为的独立影响，也就是缺氧诱导因子Prolyl羟化酶，它在细胞缺氧时启动转录级联反应；2)FMO3和CYP2B6多态性，它们是进一步的尼古丁代谢基因，可能具有重要的肝外活性。该基金的具体目标是：1)建立尼古丁代谢的综合预测遗传模型，包括所有三种尼古丁代谢途径及其相关基因，重点关注CYP2A6、UGTs和FMOs。然后将改进的模型应用于进一步的样本，以确定尼古丁代谢的遗传差异对吸烟表型的影响；2)鉴定改变尼古丁代谢基因功能的变异，并论证其作用机制。我将特别关注人类大脑和肝脏样本中的蛋白质和mRNA表达以及剪接；3)鉴定EGLN2等缺氧反应候选基因的变异，确定其对吸烟表型的影响机制。我的初步数据表明，与尼古丁依赖和香烟消费相关的EGLN2变异改变了不同EGLN2 5'UTR mRNA剪接变异的相对表达。我将在正常和缺氧条件下培养的细胞中鉴定受EGLN2基因型影响的基因和蛋白表达差异。本K01应用程序的目标是在特殊条件下获得统计人类遗传学和细胞培养方面的进一步培训，并将此专业知识应用于药物滥用问题。