Integrated GWAS of complex behavioral and gene expression traits in outbred rats

描述(由申请人提供)：我们将使用定量基因技术来识别影响与药物滥用相关的一系列心理复杂行为表型的基因和等位基因。我们的中心利用了研究设计、下一代测序和统计方法方面的许多最新进展，这些都创造了一个特殊的机会。尽管在过去的二十年里，小鼠的正向(表型到基因型)和反向(表型到表型)遗传学研究都取得了巨大的进步，但在大鼠身上开发和应用同样的技术的进展要少得多。虽然对小鼠的正向和反向遗传学研究都取得了丰硕的成果，但许多重要但复杂的心理过程很难或不可能在小鼠身上进行研究。出于这个原因，我们建议采用我们已经在小鼠身上成功使用的各种遗传技术，用于大鼠的行为研究。在目前的应用中，我们建议使用最先进的工具来阐明与药物滥用有关的各种行为的遗传基础，在4,800只大鼠中。我们中心的一个关键优势是我们利用了一种独特的大鼠异种种群(HS)。这些大鼠，有时被称为N/NIH，是1984年通过杂交8个近交系大鼠品系而产生的HS，已经作为外交种群保持了65代。这导致了大量累积的重组，使它们成为进行类似于人类基因组全关联研究(GWAS)的研究的理想资源。值得注意的是，所有8个近交系方正菌株最近都进行了重新测序，识别出720万个SNPs。我们将使用一种创新的基于下一代测序的方法对这些大鼠进行基因分型，该方法以极低的成本提供约10万个SNPs。我们将使用这些数据来推断单倍型，这将使我们能够计算出每只大鼠的全部720万个SNP。除了确定这些SNPs与行为特征之间的关联外，我们还将检查72只行为幼稚的大鼠的基因表达，重点放在四个关键的大脑区域。我们将利用这些数据来确定表达数量性状基因座(EQTL)。然后我们将整合所有这些数据，以确定影响行为的特定基因。许多正在研究的行为领域都是已知的性二形性；我们的研究将同时使用雄性和雌性大鼠，这将使我们能够通过基因相互作用来识别性别差异和性别。我们还将确定这些性状之间的共同遗传力，以及单个基因座对多个假定相关的行为领域的多效性效应。最后， 拟建的中心包括许多教育、职业发展和公共宣传活动。实施高中和本科人才培养计划。此外，技术员、研究生、博士后和初级教员将以个人发展计划和研究业绩进展报告的形式收到职业发展建议。最后，我们将参与公共外展项目，利用芝加哥、布法罗和孟菲斯的不同社区。

DESCRIPTION (provided by applicant): We will use quantitative genetic techniques to identify genes and alleles that influence a constellation of psychologically complex behavioral phenotypes that are associated with drug abuse. Our center capitalizes on a number of recent advances in study design, next-generation sequencing and statistical methods that together create an exceptional opportunity. Whereas the past two decades have seen enormous advances in both forward (phenotype to genotype) and reverse (genotype to phenotype) genetic studies in mice, there has been much less progress developing and applying the same techniques in rats. Although both forward and reverse genetic studies in mice have been extremely fruitful, many important but complex psychological processes are difficult or impossible to study in mice. For this reason we are proposing to adapt a variety of genetic techniques that we have already used successfully in mice, for behavioral studies in rats. In the current application, we propose to employ state-of-the-art tools to elucidate the genetic basis of a variety of behaviors that are relevant to drug abuse in 4,800 rats. A key strength of our center is that we utilize a unique rat heterogeneous stock (HS). These rats, sometimes referred to as N/NIH, are an HS that was created in 1984 by intercrossing 8 inbred rat strains and have been maintained as an outbred population for 65 generations. This has given rise to numerous accumulated recombinations that make them an ideal resource for performing studies that are analogous to human genome wide association studies (GWAS). Significantly, all 8 inbred founder strains have recently been re-sequenced, identifying 7.2 million SNPs. We will genotype these rats using an innovative next-generation sequencing-based method that provides ~100K SNPs at an extremely low cost. We will use these data to infer haplotypes, which will allow us to impute all 7.2 million SNPs in each rat. In addition to identifying associations between these SNPs and the behavioral traits, we will also examine gene expression in 72 behaviorally naive rats focusing on 4 key brain regions. We will use these data to identify expression quantitative trait loci (eQTLs). We will then integrate all of these data to identify specific genes that influece behavior. Many of the behavioral domains being studied are known to be sexually dimorphic; our study will use both male and female rats, which will allow us to identify sex differences and sex by genotype interactions. We will also identify co-heritability among these traits, as well as pleiotropic effects of individual loci on multiple putatively related behavioral domains. Finally, the proposed center includes numerous educational, career development and public outreach activities. We will implement a program to train high school and undergraduate students. In addition, technicians, graduate students, postdocs and junior faculty will receive career development advice in the form of individual development plans and research performance progress reports. Finally, we will engage in public outreach programs that will draw on diverse communities in Chicago, Buffalo and Memphis.