Gene-environment interactions and their impact on human health

Abstract

The molecular processes underlying human health and disease are highly complex. Often, genetic and environmental factors contribute to a given disease or phenotype in a non-additive manner, yielding a gene-environment (G × E) interaction. In this work, we broadly review current knowledge on the impact of gene-environment interactions on human health. We first explain the independent impact of genetic variation and the environment. We next detail well-established G × E interactions that impact human health involving environmental toxicants, pollution, viruses, and sex chromosome composition. We conclude with possibilities and challenges for studying G × E interactions.

Fig. 1. Gene × environment (G × E) interactions involve synergy between environmental risk factors and genetic variants.

Some G × E interactions can increase the risk of disease. A model of G × E interaction originally defined in Ottman [8] and further refined in Kauffmann and Demenais [9] is depicted where the genetic risk variants and one or more environmental risk factor synergistically affect disease risk.