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QTL研究的因子模型

Factor models for QTL studies
课程网址: http://videolectures.net/licsb08_stegle_fmq/  
主讲教师: Oliver Stegle
开课单位: 马克斯普朗克研究所
开课时间: 2008-04-17
课程语种: 英语
中文简介:
最近可获得的大规模数据集分析了不同人群中的单核苷酸多态性(SNP)和基因表达,已经引起了很多关注,发现了遗传变异模式及其与基因调控的关联。表达谱的性质的两个方面使得识别和解释这种关联变得困难。首先,我们期望各种环境,发育和其他因素影响基因表达,这可能会掩盖这种联系。其次,连接基因的监管网络使得难以确定SNPS与监管要素之间的因果关系。  我们通过提出FA-eQTL来解决第一个问题,FA-eQTL是一个明确考虑非遗传变异性的因子模型,因此可以显着提高表达数量性状基因座(eQTL)研究的能力。  我们讨论了该模型的变分贝叶斯实现,并指出了适用于某些情况的快速近似。将我们的模型应用于模拟和现实世界数据,我们可以证明性能的显着提高。根据HapMap项目的数据,我们发现重要关联的数量是标准eQTL方法的三倍以上。  为了解决基因的共表达,我们通过共同降低表达谱的维度和对非遗传因素建模来进一步扩展FA-eQTL。我们讨论将这种增强的QTL模型应用于生物数据的结果,包括人类以及来自酵母的数据集。
课程简介: The recent availability of large scale data sets profiling single nucleotide polymorphisms (SNPs) and gene expression across different human populations, has directed much attention towards discovering patterns of genetic variation and their association with gene regulation. Two aspects of the nature of expression profiles make the identification and interpretation of such associations difficult. Firstly, we expect that a variety of environmental, developmental and other factors influence gene expression which can obscure such associations. Secondly, the regulatory network linking genes makes it difficult to pinpoint causal relationships between SNPS and regulatory elements. We address the first issue by proposing FA-eQTL, a factor-model that explicitly takes non-genetic variability into account, and thereby can significantly improve the power of an expression Quantitative Trait Loci (eQTL) study. We discuss a variational Bayesian implementation of this model, and point out rapid approximations that are applicable in certain situations. Applying our model to simulated and real world data we can demonstrate a significant improvement in performance. On data from the HapMap project, we find more than three times as many significant associations than a standard eQTL method. To address co-expression of genes, we further extended FA-eQTL by jointly reducing the dimensionality of the ex-pression profile and modelling non-genetic factors. We discuss results applying this enhanced QTL-model to biological data, including human as well as datasets from yeast.
关 键 词: 大规模数据集; 遗传变异模式; 基因调控; 数量性状基因座
课程来源: 视频讲座网
最后编审: 2020-07-31:yumf
阅读次数: 67