Epigenetic variability in the human oxytocin receptor (OXTR) gene: A possible pathway from early life experiences to psychopathologies

The human oxytocin (OXT) system is implicated in the regulation of complex social behaviors, as well as in psychopathologies characterized by social deficits. Emerging evidence suggests that variation in epigenetic regulation of the oxytocin receptor gene (OXTR) provides the oxytocin system with flexibility in response to environmental events, especially those occurring during early childhood. Changes in DNA methylation patterns of OXTR associated with these events may reflect biological alterations of social sensitivity. This is often related to an increased risk of developing mental disorders later in life. Here, we systematically reviewed all human studies (n = 30) discussing OXTR methylation in relation to socio-behavioral phenotypes. As such, we provide a complete and up-to-date overview of the literature that will aid future research in the interdisciplinary field of epigenetics and socio-behavioral sciences.