Presented By:

David Moore, Ph.D.

Professor, Department of Psychology

Pitzer College

Abstract

Molecular biologists have known for decades that what matters is not the genes you have, but rather how you use them; because genes can be “turned on” and “turned off,” the mere presence of a gene in a genome tells you little about the phenotypic outcomes that can be expected. We have begun to understand how “epigenetic” modifications to DNA can alter genetic expression, and it has become clear that our day-to-day experiences influence these modifications, and therefore our psychological and biological characteristics. Among the factors that influence our epigenetic states are our diets and exposure to stressful events. Although many researchers are interested in epigenetics because epigenetic phenomena can be associated with disease states, behavioral scientists interested in normal development have reason to attend to advances in this field, too; epigenetic events, for example, appear to influence learning and memory, and might help explain why twins with identical genomes nonetheless typically differ from one another. Finally, the finding that some epigenetic modifications can be transmitted across generations has led some theorists to begin rethinking the role of so-called “acquired characteristics” in evolution. Such discoveries have generated an enormous amount of excitement in disciplines as disparate as psychology, oncology, nutrition, and philosophy, and there can be little doubt that as our thinking about human nature changes to accommodate these discoveries, our thinking about public policies will be influenced as well.