Evolving Methods in Genetic Epidemiology. III. Gene-Environment Interaction in Epidemiologic Research

Effects on disease risk Genotype In the absence of envlronmentf No effect, Khoury et al. (24). t R, = disease risk among persons with exposure without genotype, divided by disease risk among persons with no exposure and no susceptible genotype; and R g = disease risk among persons with genotype without exposure, divided by disease risk among persons with no exposure and no susceptible genotype.