A systems biology approach for identifying novel pathway regulators in eQTL mapping.

Expression quantitative trait loci (eQTL) mapping holds great promise in elucidating gene regulations and predicting gene networks associated with complex phenotypes. We propose a systems biology approach by incorporating prior pathway information into an eQTL mapping framework, to identify novel pathway regulators that mediate pathway expression changes. We model gene expressions in a predefined biological pathway as a multivariate response to test the joint variation changes among different genotype categories at a locus. The method is motivated and applied to a yeast data set. Significant pathway regulators and regulation hotspots are detected. The proposed method provides a powerful tool for understanding gene regulation at a pathway level.