A0533
Title: Identification of trans-eQTLs using mediation analysis with multiple mediators
Authors: Nayang Shan - Tsinghua University (China)
Zuoheng Wang - Yale University (United States) [presenting]
Lin Hou - Tsinghua University (China)
Abstract: Identification of expression quantitative trait loci (eQTLs) advances understanding of genetics and regulatory mechanisms of gene expression in various organisms. Previous studies suggest that trans-eQTLs may regulate expression of remote genes by altering the expression of nearby genes. Trans-association has been studied in the mediation analysis with a single mediator. However, prior applications with one mediator are prone to model misspecification due to correlations between genes. Motivated from the observation that trans-eQTLs are more likely to associate with more than one cis-gene than randomly selected SNPs in the GTEx dataset, we developed a computational method to identify trans-eQTLs that are mediated by multiple mediators. In simulation studies, multiple mediator analysis had increased power to detect mediated trans-eQTLs, especially in large samples. In the HapMap3 data, we identified 11 mediated trans-eQTLs that were not detected by the single mediator analysis in the combined samples of African populations. Moreover, the mediated trans-eQTLs in the HapMap3 samples are more likely to be trait-associated SNPs. Our approach has improved the power of detecting mediated trans-eQTLs and advanced knowledge of gene regulation.
