Human Genome + Human Exposome = Your Health

Elise Miller, MEd

In the push towards personalized medicine, unlocking the human genome is often lauded as the key to developing individualized medical plans for those who have genes indicating they are at risk of certain diseases or disabilities.

Those plans often include developing and using more and more pharmaceuticals. The increasing mixture of pharmaceuticals ending up in soil and waterways is associated with a growing number of environment and health problems, a situation expected to be made worse with climate change as reported this month in the Journal of Toxicology and Environmental Health.

Even more important, this view overlooks the fact that epigenetic markers, influenced by a range of environmental factors, are also crucial to understanding a person’s susceptibility to disease. Given this, a number of researchers have recently pressed for a significant investment in mapping the human exposome—that is, all environmental exposures starting from conception, including nutritional, chemical, psychosocial, etc. These researchers include Christopher Wild, PhD, a cancer epidemiologist who coined the term ‘exposome’, and others at various institutions in the US, such as the National Institutes of Health, Centers for Disease Control and Prevention, University of California-Berkeley, Emory University, and so forth. Granted this is a much more complex undertaking than mapping the human genome because of the multiple interacting environmental factors that can influence gene expression and, in turn, health across the lifespan. But without a dedicated effort to explore the exposome, we will continue to focus solely on the genome, which is only part (and likely just a small part) of the equation when understanding human health.

On the other hand, if health professionals not only know a person’s DNA, but what that person has been exposed to in terms of stress, chemicals, diet, etc. as well, then they will be far better able to reduce risk and prioritize prevention. For example, widespread use of electronic health records provides an opportunity to develop standardized questions about people’s exposures. Since early life development influences health across the lifespan, obstetric records might be a good place to start. Not only would this enhance health professionals’ ability to make recommendations early on, it would provide a database for studying correlations between exposures and diseases that appear later in life–and in turn, radically increase options for improving individual and public health.

To learn more about the current scientific understanding of the human exposome, please join us and our research experts on CHE’s Partnership call to be held Wednesday September 18th. For details and to RSVP, please see

As the days shorten and the leaves enliven the ground with their golden tones, I look forward to staying in touch and deepening our collaborative efforts this fall.