OXTR and perinatal asphyxia: The gene that codes for the oxytocin receptor (OXTR) is susceptible to stress-related epigenetic regulation of gene expression (Kumsta et al. 2013; Kraaijenvanger et al. 2019), and that mothers with perinatal depression have elevated DNA methylation at OXTR compared with mothers with no perinatal depression (King et al. 2017).