Early life deprivation and stress can leave lasting marks on both physiology and behavior. In this study, Awalt et al. (2024) examined how adverse early experiences affect epigenetic regulation and attachment in domestic dogs, a species that shares human environments and social-cognitive traits.
The researchers studied 47 owner-dog pairs, including rescued dogs with histories of abuse or neglect, alongside matched control dogs. They analyzed DNA methylation of two key receptor genes: glucocorticoid receptor (NR3C1), linked to stress regulation, and oxytocin receptor (OXTR), associated with bonding and social behavior. Dogs were also tested in an attachment paradigm involving separation events, while cortisol levels and behavioral responses were measured.
Results showed that dogs with adverse life histories displayed altered methylation patterns. NR3C1 methylation varied with age and was tied to cortisol reactivity, while OXTR methylation was lower in stressed dogs but predicted insecure attachment styles. These patterns indicate that early stress disrupts the hypothalamic-pituitary-adrenal (HPA) axis and leads to enduring differences in emotional regulation.
The findings underscore the long-term impact of early adversity on dogs’ biology and behavior. Just as in humans, early experiences can shape emotional resilience, stress regulation, and attachment security, highlighting the importance of supportive environments for puppies and rescued dogs.
Source: Awalt, S. L., Boghean, L., Klinkebiel, D., & Strasser, R. (2024). A dog’s life: Early life histories influence methylation of glucocorticoid (NR3C1) and oxytocin (OXTR) receptor genes, cortisol levels, and attachment styles. Developmental Psychobiology, 66(3), e22482. Published March 14, 2024.
