Genetic Modulation of Glaucoma

在这个建议中，我们使用我们扩大的BXD重组近交系来鉴定基因位点， 参与调节青光眼的严重程度。我们的方法结合了全面的临床和实验室 检查，和微阵列分析的81个BXD系在过去10年中产生的整个集合， 表达了研究眼病和青光眼遗传学的目的。BXD的亲本菌株之一， DBA/2 J，发展为年龄相关性青光眼，之前有虹膜萎缩和色素分散。而 两个基因Tryp 1和Gpnmb的突变等位基因导致D2的虹膜疾病，文献强烈表明， 这些突变不足以引起青光眼。具体地，将两种突变等位基因渐渗到 C57 BL/6 J是BXD的另一个亲本菌株，对视神经损伤具有显著的抗性。这表明 除了那些引起色素分散的基因外，其他基因也会影响青光眼的表型。当前 提案描述了一个独特的机会来定义修饰位点。在目标1中，我们测试了假设， Tryp 1和Gpnmb的组合突变不足以引起青光眼表型的所有方面。如果 我们的假设是正确的，我们希望看到疾病的严重程度不仅仅取决于两个突变体， 等位基因我们已经鉴定了多个BXD菌株，其中IOP和遗传双倍型不相关。 当我们系统地检查所有BXD菌株并建立表型和双体型之间的关系时， 完全期望找到其他菌株，违背了简单的两个基因座疾病模型的期望。在目标2中， 确定调节青光眼严重程度的基因座和基因。为此，我们将确定和评估候选人 调节青光眼表型严重程度的基因座内的基因。我们将利用我们的新整体 D2的基因组鸟枪测序（2009年UTHSC产生的短读段覆盖率约> 50倍），连同沿着 作为这项工作的前奏，我们还生成了大量的全眼和全视网膜表达数据集。 我们希望利用最先进的生物信息学技术有效地提名和评估候选青光眼基因。 方法和常规分子测定。在目标3中，我们使用双向翻译。我们测试的 使用人类青光眼患者的群组对来自Aim 2的小鼠候选物的翻译有效性进行验证。J. Wiggs博士 和同事们将使用提名的候选青光眼基因进行集中的基因关联研究， 目标2.具体地说，我们使用的关联分析的标志物涵盖同线区域的人类 染色体在相互反向翻译中，我们（MMJ和LL）将评估已知、新和候选 青光眼基因，并确定这些变异是否以及如何与青光眼相关- BXD中的相关特征。结合小鼠和人类青光眼的最优先候选基因 研究，我们将产生易感性候选基因的分子和统计模型， 表型和相关机制。

In this proposal, we use our enlarged set of BXD recombinant inbred strains to identify gene loci that are involved in modulating the severity of glaucoma. Our approach combines a thorough clinical and laboratory examination, and microarray analysis of the entire set of 81 BXD lines generated over the last 10 years with the express purpose of studying the genetics of eye disease and glaucoma. One of the parental strains of BXD, DBA/2J, develop an age-related glaucoma that is preceded by iris atrophy and pigment dispersion. While mutant alleles of two genes, Tryp1 and Gpnmb, cause the iris disease in D2, the literature strongly suggests that these mutations are not sufficient to cause glaucoma. Specifically, introgression of both mutant alleles onto C57BL/6J, the other parent strain of BXD, results in a marked resistance to optic nerve damage. This indicates that genes other than those that cause pigment dispersion influence the glaucomatous phenotype. The current proposal describes a unique opportunity to define the modifying loci. In Aim 1, we test the hypothesis that the combined mutations in Tryp1 and Gpnmb are not sufficient to cause all aspects of the glaucoma phenotype. If our hypothesis is true, we expect to see that the severity of disease is not solely dependent on the two mutant alleles. We have already identified multiple BXD strains in which IOP and genetic diplotype are not correlated. As we systematically examine all BXD strains and establish relations between phenotype and diplotype, we fully expect to find additional strains that defy expectations of a simple two-locus disease model. In Aim 2, we define loci and genes that modulate glaucoma severity. To do so, we will identify and evaluate candidate genes within loci that modulate the severity of the glaucoma phenotype. We will exploit our new whole genome shotgun sequence for D2 (about >50x short read coverage generated at UTHSC in 2009) along with massive whole eye and whole retina expression datasets that we have also generated as a prelude to this work. We expect to efficiently nominate and evaluate candidate glaucoma genes using state-of-the-art bioinformatic methods and conventional molecular assays. In Aim 3, we use bidirectional translation. We test the translational validity of mouse candidates from Aim 2 using cohorts of human glaucoma patients. Dr. J. Wiggs and colleagues will perform focused gene association studies using candidate glaucoma genes nominated in Aim 2. Specifically, we use association analyses of markers encompassing syntenic regions of human chromosomes. In reciprocal reverse translation, we (MMJ and LL) will evaluate known, new, and candidate glaucoma genes from clinical cohorts and determine if and how these variants are associated with glaucoma- associated traits in BXDs. Combining the top priority gene candidates from both mouse and human glaucoma studies, we will generate molecular and statistical models of susceptibility candidate genes, linked phenotypes, and associated mechanisms.