title: Method for indirectly estimating gene-environment effect modification and power given only genotype frequency and odds ratio of environmental exposure.
abstract: Both genes and environment are important determinants of disease. In this paper we model gene-environment effect modification on the odds ratio scale OR(GEID) and show how to indirectly estimate the effect and 95% confidence intervals (CI) for the simple case of no main genetic and environmental effects [i.e., OR(GE/D) = OR(GE/D) = 1]. A statistic is presented to test the null hypothesis OR(GE/D) = 1 and to calculate corresponding power, given the odds ratio for environmental exposure OR(E/D) and population genotype frequency (g). Direct extension of the above model provides a mathematical framework for estimating confidence bounds in more complex cases involving partial genetic and/or environmental effects.
authors.affiliation: John A. Burns School of Medicine, University of Hawai'i at Manoa, 1960 East-West Road, Room T201b, Honolulu, HI 96822-2319, USA. Jimmy.efird@stanfordalumni.org
authors.forename: Jimmy Thomas
authors.initials: JT
authors.lastname: Efird
mesh_terms: D016001:Confidence Intervals; D004198:Disease Susceptibility / Q000453:epidemiology / Q000209:etiology*; D004781:Environmental Exposure; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008433:Mathematics; D016017:Odds Ratio