Method for indirectly estimating gene-environment effect modification and power given only genotype frequency and odds ratio of environmental exposure.

Jimmy Thomas Efird

doi:10.1007/s10654-005-2018-3

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Method for indirectly estimating gene-environment effect modification and power given only genotype frequency and odds ratio of environmental exposure.

Jimmy Thomas Efird

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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.

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Confidence Intervals Disease Susceptibility Environmental Exposure Gene Frequency Genotype Humans Mathematics Odds Ratio Journal Article Research Support, N.I.H., Extramural Research Support, U.S. Gov't, P.H.S.

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Jimmy Thomas Efird. 2005. Method for indirectly estimating gene-environment effect modification and power given only genotype frequency and odds ratio of environmental exposure.. https://doi.org/10.1007/s10654-005-2018-3

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