Functional Genomics of Psoriasis

描述（由申请人提供）：最近的银屑病全基因组关联研究（GWAS）已经确定了41个银屑病易感位点，我们目前正在应用多种遗传和基因组资产进行银屑病的分子遗传解剖，这为鉴定PsC和PsA的因果变异提供了一个独特的强大平台。发现疾病相关遗传变异的功能基础是分析牛皮癣和所有复杂遗传疾病的疾病关联的主要目标，因为它提供了基因型和表型之间的分子联系。然而，到目前为止，在牛皮癣以及其他复杂的遗传疾病中，与疾病相关的变异特异性功能的令人信服的证明并不常见。在许多情况下，这是由于功能变异的不完整和/或不准确的确定。我们将在我们独特的数据集上带来的统计专业知识将允许更好地定义功能研究的分子靶标。此外，我们的实验室在角化细胞生物学和免疫学方面拥有强大的专业知识，为鉴定变异的功能探索提供了补充平台。最后，值得注意的是，个体变异的功能分析并不是本研究的唯一目标。为了通过开发新疗法使患者受益并实现个性化医疗的承诺，严格识别它们所描述的分子途径至关重要。基于这些考虑，我们提出了一个假设，即个体遗传变异的功能和它们所描述的途径可以通过使用当前或即将获得的数据来识别，给出了一个综合的方法，整合了与牛皮癣相关的生物统计学和生物学专业知识。为了验证这一假设，我们提出以下具体目标：使用新颖的统计工具准确识别银屑病的因果变异候选。这将通过(a)申请多轮来完成

DESCRIPTION (provided by applicant): Recent genome-wide association studies (GWAS) of psoriasis have identified 41 psoriasis susceptibility loci, and we are currently applying multiple genetic and genomic assets to the molecular genetic dissection of psoriasis, which provide a uniquely powerful platform for identification of causal variants in PsC and PsA. Finding the functional basis of disease-associated genetic variation is a major goal in the analysis of disease associations in psoriasis and all complex genetic disorders, because it provides a molecular link between genotype and phenotype. To date, however, convincing demonstration of disease associated variant-specific function is uncommon in psoriasis as well as in other complex genetic disorders. In many instances, this has been due to incomplete and/or inaccurate determination of the functional variants. The statistical expertise that we will bring t bear on our unique datasets will allow much better definition of molecular targets for functional studies. Moreover, our laboratories have strong expertise in keratinocyte biology and immunology, providing complementary platforms for the functional exploration of identified variants. Finally, it is important to note that functional analysis of individual variants is not te only goal of this research. In order to benefit patients via the development of new therapies and fulfill the promise of personalized medicine, it is of key importance to rigorously identify the molecular pathways that they delineate. Based on these considerations, we advance the hypothesis that the functions of individual genetic variants and the pathways they delineate can be identified, using currently or soon-to-be available data, given an integrated approach that integrates biostatistical and biological expertise relevant to psoriasis. To test this hypothesis, e propose the following specific aims: 1. To accurately identify causal variant candidates in psoriasis using novel statistical tools. This will be accomplished by (a) applying multiple rounds of conditional analysis and preferential linkage disequilibrium (PLD) analysis to GWAS-IChip meta-analysis, targeted resequencing, PsA GWAS, and exome array datasets; (b) expanded analysis of MHC differences between PsA and PsC; and (c) further analysis of identified variants in an expanded sample. 2. To systematically predict the potential effects of the disease-associated variants identified in Aim 1. This will be accomplished by (a) prediction of functional effects of newly-identified coding variants; (b) systematic assessment of non-coding variants utilizing the ENCODE database; (c) utilization of our RNASeq data for assessment of the effects of candidate cis-acting variants; and (d) systematic assessment of pathways likely to connect multiple variants in functional terms. 3. Functional testing of identified variants using a keratinocyte (KC)-based platform. This will be accomplished by measurement of signal transduction responses as a function of genotype for the D10N variant in TRAF3IP2 using (a) normal human keratinocytes (NHK) harvested from individuals bearing different TRAF3IP2 genotypes and (b) transfection of "wild type" vs variant alleles into immortalized KC with or without silencing of endogenous TRAF3IP2. We will also (c) extend this approach to predicted damaging variants identified from Aims 1 and 2 as likely to be important in KC. 4. Functional testing of identified variants using a blood-based, living-cell platform. This will be accomplished by (a) separation of monocytes and T-cells from the blood of individuals of known genotypes for the P1104A and I684S variants in TYK2, followed by measurement of signal transduction responses as a function of genotype. We will also (b) extend these studies to predicted damaging variants at other loci identified from Aims 1 and 2 as likely to be important in immunocytes.