What do we need to know prior to thinking about incorporating an epigenetic evaluation into safety assessments?

The International Life Sciences Institute, Health and Environmental Sciences Institute sponsored a workshop entitled "State of the Science: Evaluating Epigenetic Changes," hosted by the National Institute of Environmental Health Sciences, Research Triangle Park, NC, 28-30 October 2009. The goal was to evaluate and enhance the scientific knowledge base regarding epigenetics and its role in disease, including potential relationships between epigenetic changes and transgenerational effects. A distinguishing aspect of the workshop was the highly interactive discussion session on the final morning. Meeting participants formed breakout groups (with representation from academia, industry, and government in each group) and were tasked with integrating their previous knowledge of epigenetics with what was learned during the workshop. The participants addressed the issue of what needs to be known prior to thinking about incorporating an epigenetic evaluation into safety assessment. To this end, the breakout groups were asked to address the following questions: (1) What model systems might be employed to evaluate the ability of a chemical to produce an epigenetic change (affecting the F1 and/or F3 generation); (2) What end points/targets might be evaluated; (3) What techniques might be employed; and (4) Regulatory Perspective: When is it appropriate to incorporate "new" science, in this case epigenetics, into the regulatory process? What does one need to know, what are the pitfalls and how might these be overcome/avoided? The basis of this paper is a synopsis of these discussions. The workshop highlighted the fact that the field of epigenetics is evolving at a very rapid pace and indicated that a great deal needs to be learned prior to being able to rationally incorporate an epigenetic evaluation into safety assessment. The value of the workshop is that it called attention to key data/knowledge gaps that should serve to focus attention on the areas where research and new thinking are needed to better understand epigenetics and its relationship to safety assessment.