Epigenetic Signatures as Biomarkers of Exposure

To advance our knowledge of the influence of environmental exposures on human health and disease, robust studies are needed. However, for many exposures, robust studies are not feasible due to limitations with current ascertainment methods and/or study designs. Epigenetics, the study of mitotically heritable, reversible information that regulates critical cell processes, has gained much attention because it offers a potential mechanism to explain how exposures can influence cell states. Therefore, most studies have focused on epigenetics as a mechanism for disease. However, emerging evidence also suggests that epigenetic marks may also serve as biomarkers of exposure. Here, we highlight findings showing that the epigenome is labile to the environment and that these exposure-associated changes show long-term stability, are specific, are detectable in accessible tissues, can predict exposure status, and can be practically implemented, thus supporting the potential for epigenetic patterns to serve as robust measures of environmental exposure.