Genes, Behavior, and the Social Environment: Moving Beyond the Nature/Nurture Debate

During the twentieth century, great strides were made in reducing dis- ease and improving the health of individuals and populations. Public health measures such as sanitation, improved hygiene, and vaccines led to major reductions in mortality and morbidity (Turnock, 2001). Increased attention to the hazards of the workplace resulted in reduced injuries and better health for workers (IOM, 2003a). Advances in biomedical research helped expand knowledge of disease and spurred the development of new clinical and pharmaceutical interventions. More recently, the sequencing of the human genome has provided information that holds the promise for further improving human health.

Over the years a large body of evidence has emerged indicating that social and behavioral factors such as socioeconomic status, smoking, diet, and alcohol use are important determinants of health (Berkman and Kawachi, 2000; IOM, 2000; Marmot and Wilkinson, 2006). Recent studies also suggest that examining interactions among genetic and social- environmental factors could greatly enhance understanding of health and illness. For example, Caspi and colleagues (2003) found “evidence of a gene- by-environment interaction, in which an individual’s response to environmental insults is moderated by his or her genetic makeup.” In a study showing how the social environment can influence biological response, Manuck et al. (2005) found that the socioeconomic status of communities is associated with variations in central nervous system serotonergic responsivity, which may have implications for the prevalence of psychological disorders and behaviors such as depression, impulsive aggression, and suicide 

As part of a strategy to determine how best to integrate research priori- ties to include an increased focus on the impact on health of interactions among social, behavioral, and genetic factors, the National Institutes of Health (NIH), Office of Behavioral and Social Sciences Research, in con- junction with the National Human Genome Research Institute and the National Institute of General Medical Sciences, requested that the Institute of Medicine undertake a study to examine the state of the science on gene- environment interactions that affect human health, with a focus on the social environment.1 The goal of the study was to identify approaches and strategies to strengthen the integration of social, behavioral, and genetic research and to consider the relevant training and infrastructure needs. More specifically, NIH requested the following:

1. Review the state of the science on the interactions between the social environment and genetics that affect human health.

2. Develop case studies that will demonstrate how the interactions of the social environment and genetics affect health outcomes; illustrate the methodological issues involved in measuring the interactions; elucidate the research gaps; point to key areas necessary for integrating social, behavioral, and genetic research; and suggest mechanisms for overcoming barriers.

3. Identify gaps in the knowledge and barriers that exist to integrating social, behavioral, and genetic research in this area.

4. Recommend specific short- and long-term priorities for social and behavioral research on gene-social environment interactions; identify mechanisms that can be used to encourage interdisciplinary research in this area.

5. Assess workforce, resource, and infrastructure needs and make ac- tionable recommendations on overcoming barriers and developing mechanisms to accelerate progress.