Title: A Unified Model for the Analysis of Gene-Environment Interaction.
Authors: Gauderman, W James; Kim, Andre; Conti, David V; Morrison, John; Thomas, Duncan C; Vora, Hita; Lewinger, Juan Pablo
Published In Am J Epidemiol, (2019 04 01)
Abstract: Gene-environment (G × E) interaction is important for many complex traits. In a case-control study of a disease trait, logistic regression is the standard approach used to model disease as a function of a gene (G), an environmental factor (E), G × E interaction, and adjustment covariates. We propose an alternative model with G as the outcome and show how it provides a unified framework for obtaining results from all of the common G × E tests. These include the 1-degree-of-freedom (df) test of G × E interaction, the 2-df joint test of G and G × E, the case-only and empirical Bayes tests, and several 2-step tests. In the context of this unified model, we propose a novel 3-df test and demonstrate that it provides robust power across a wide range of underlying G × E interaction models. We demonstrate the 3-df test in a genome-wide scan of G × sex interaction for childhood asthma using data from the Children's Health Study (Southern California, 1993-2001). This scan identified a strong G × sex interaction at the phosphodiesterase gene 4D locus (PDE4D), a known asthma-related locus, with a strong effect in males (per-allele odds ratio = 1.70; P = 3.8 × 10-8) and virtually no effect in females. We describe a software program, G×EScan (University of Southern California, Los Angeles, California), which can be used to fit standard and unified models for genome-wide G × E studies.
PubMed ID: 30649161
MeSH Terms: Asthma/genetics; Bayes Theorem; Case-Control Studies; Child; Cyclic Nucleotide Phosphodiesterases, Type 4/analysis; Female; Gene-Environment Interaction*; Genome-Wide Association Study; Humans; Male; Models, Genetic*; Software