We covered a lot of ground in this article (see abstract below). What I want to highlight here is the model we articulated for the integration of genetic epidemiology and social epidemiology. You can find the full paper here.
Genetics and Social Gradients in Health
It is clear that ill health and poverty are correlated. It also clear that causality flows in both directions; ill health is impoverishing, and poverty is unhealthy. Thus, there are 3 models that describe how genetic risks might contribute to socioeconomic gradients in health.
- No contribution: genetic and environmental risks are additive. Genetic risks are equally distributed across the social gradient. Social gradients in health are entirely caused by environmental factors ( left column). We view this as the null hypothesis.
- Gene-environment correlation (rGE): genetic risks are not equally distributed across the social gradient. Differences in health outcomes arise from the higher burden of genetic risk at the lower end of the social gradient (middle column).
- Gene-environment interaction (GxE): genetic risks are equally distributed across the social gradient. Differences in health outcomes arise from exacerbating effects of environmental risks concentrated at the lower end of the social gradient and also from mitigating or protective effects of environmental assets concentrated at the upper end of the social gradient (right column).