Risk and Resilience: Genetic and Environmental Influences on Development of the Stress Response

• Authors: Charles Gillespie, Emory University; Justine Phifer, Emory University; Bekh Bradley-Davino, Emory University; Kerry Ressler, Emory University
• Journal Title: Depression and Anxiety
• Volume: Volume 26, Number 11
• Publisher: Wiley: 12 months | 2009-11, Pages 984-992
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1002/da.20605
• Subjects: Psychology, General; Psychology, Psychobiology; Health Sciences, General
• Keywords: Post-traumatic Stress Disorder; Depression; socioeconomic status; Trauma; Child Abuse; Childhood Maltreatment; amygdala

Abstract

Exposure to stressful events during development has consistently been shown to produce long-lasting alterations in the hypothalamic-pituitary-adrenal (HPA) axis, which may increase vulnerability to disease, including PTSD and other mood and anxiety disorders. Recently reported genetic association studies indicate that these effects may be mediated, in part, by gene x environment (GxE) interactions involving polymorphisms within two key genes, CRHR1 and FKBP5. Data suggest that these genes regulate HPA axis function in conjunction with exposure to child maltreatment or abuse. In addition, a large and growing body of preclinical research suggests that increased activity of the amygdala-HPA axis induced by experimental manipulation of the amygdala mimics several of the physiological and behavioral symptoms of stress-related psychiatric illness in humans. Notably, interactions between the developing amygdala and HPA axis underlie critical periods for emotional learning which are modulated by developmental support and maternal care. These translational findings lead to an integrated hypothesis: high levels of early life trauma lead to disease through the developmental interaction of genetic variants with neural circuits that regulate emotion, together mediating risk and resilience in adults.