‘Our biology is listening’: biomarkers as molecular vestiges of early life and the production of positive childhood experiences in behavioral epigenetics

The sciences of environmental epigenetics and the Developmental Origins of Health and Disease have become central in efforts to understand how early life experiences impact health across the life course. This paper draws on interviews with epigenetic scientists and laboratory observations in the United States and Canada to show how scientists conceptualize epigenetic biomarkers as <i>molecular vestiges of early life</i> and the consequences this has for postgenomic approaches to health, risk, and intervention. We argue that this process demarcates early life as the optimal time to study and intervene in health and positions biomarkers as conceptual and methodological tools that scientists mobilize to reimagine early life environments. These environments include Positive Childhood Experiences (PCEs), which reflect an emergent and increasingly prominent epistemic object in behavioral epigenetics. Though distinct from widespread research on Early Life Adversity, we show how PCEs continue to essentialize experience in gendered and individualized ways. Further, this paper suggests that focusing on biomarkers as molecular vestiges of early life allows scientists to create stability despite ongoing epistemological and biological unknowns in epigenetics and DOHaD. Our findings contribute new perspectives to social studies of epigenetics, biomarkers, and the production of novel epistemic objects in postgenomic knowledge practices.