Genetic Modulation of Glaucoma

在这项建议中，我们使用我们扩大的BXD重组近交系菌株集来鉴定 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 对在过去10年中用 表达研究眼病和青光眼遗传学的目的。BXD的亲本菌株之一， DBA/2J导致年龄相关性青光眼，在此之前会出现虹膜萎缩和色素弥散。而当 两个基因Tryp1和GPNMB的突变等位基因导致D2的虹膜疾病，文献强烈表明 这些突变不足以导致青光眼。具体地说，两个突变等位基因都导入到 BXD的另一个亲本株C57BL/6J对视神经损伤有明显的抵抗力。这表明 导致色素分散的基因以外的基因会影响青光眼的表型。海流 提案描述了定义修饰基因座的独特机会。在目标1中，我们测试假设 Tryp1和GPNMB的联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并不完全取决于这两个突变 等位基因。我们已经发现了多种BXD菌株，在这些菌株中，眼压和遗传二倍型没有相关性。 当我们系统地检查所有BXD菌株并建立表型和二倍型之间的关系时，我们 完全可以期待发现更多的毒株，这些毒株违背了简单的双基因座疾病模型的预期。在目标2中，我们 定义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 基因座内调节青光眼表型严重程度的基因。我们将开发我们的新产品 D2的基因组鸟枪序列(约50倍短读报道，由UTHSC于2009年生成)以及 我们还生成了大量的整个眼睛和整个视网膜的表情数据集，作为这项工作的前奏。 我们希望使用最先进的生物信息学有效地提名和评估候选青光眼基因 方法和常规的分子检测方法。在目标3中，我们使用双向翻译。我们测试了 利用人类青光眼患者队列研究来自AIM 2的候选小鼠的翻译有效性。J·威格斯博士 和同事们将使用提名的候选青光眼基因进行重点基因关联研究 目的2.具体地说，我们使用围绕人类共线区域的标记的关联分析 染色体。在互反翻译中，我们(MMJ和LL)将评估已知、新和候选 来自临床队列的青光眼基因，并确定这些变异是否以及如何与青光眼相关- BXD中的相关性状。结合来自小鼠和人类青光眼的最优先候选基因 研究，我们将产生易感候选基因的分子和统计模型，链接 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.