Epigenetic modification of OXT and human sociability

• Type of Material: Article
• Authors: Brian W. Haas, University of Georgia; Megan M. Filkowski, University of Georgia; R. Nick Cochran, University of Georgia; Lydia Denison, Emory University; Alexandra Ishak, Stanford University; Shota Nishitani, Emory University; Alicia Smith, Emory University
• Language: English
• Date: 2016-07-05
• Publisher: National Academy of Sciences
• Publication Version: Final Published Version
• Copyright Statement: Copyright © 2020 National Academy of Sciences.
• Final Published Version (URL): http://dx.doi.org/10.1073/pnas.1602809113
• Title of Journal or Parent Work: Proceedings of the National Academy of Sciences
• ISSN: 0027-8424
• Volume: 113
• Issue: 27
• Start Page: E3816
• End Page: E3823
• Keywords: oxytocin; Multidisciplinary Sciences; I OXT; OXT; BEHAVIOR; Science & Technology - Other Topics; FACIAL EXPRESSIONS; BRAIN; OXYTOCIN RECEPTOR GENE; EMOTION RECOGNITION; VOXEL-BASED MORPHOMETRY; SUPERIOR TEMPORAL SULCUS; epigenetics; Science & Technology; DNA METHYLATION; SOCIAL-PERCEPTION; sociability; social cognition
• Research Categories: Biology, Neuroscience; Psychology, Clinical

Abstract

Across many mammalian species there exist genetic and biological systems that facilitate the tendency to be social. Oxytocin is a neuropeptide involved in social-approach behaviors in humans and others mammals. Although there exists a large, mounting body of evidence showing that oxytocin signaling genes are associated with human sociability, very little is currently known regarding the way the structural gene for oxytocin (OXT) confers individual differences in human sociability. In this study, we undertook a comprehensive approach to investigate the association between epigenetic modification of OXT via DNA methylation, and overt measures of social processing, including self-report, behavior, and brain function and structure. Genetic data were collected via saliva samples and analyzed to target and quantify DNA methylation across the promoter region of OXT. We observed a consistent pattern of results across sociability measures. People that exhibit lower OXT DNA methylation (presumably linked to higher OXT expression) display more secure attachment styles, improved ability to recognize emotional facial expressions, greater superior temporal sulcus activity during two social-cognitive functional MRI tasks, and larger fusiform gyrus gray matter volume than people that exhibit higher OXT DNA methylation. These findings provide empirical evidence that epigenetic modification of OXT is linked to several overt measures of sociability in humans and serve to advance progress in translational social neuroscience research toward a better understanding of the evolutionary and genetic basis of normal and abnormal human sociability.