Associations Between Oxytocin Receptor Gene (OXTR) Polymorphisms, Childhood Trauma, and Parenting Behavior

Maternal oxytocin is connected to aspects of parenting including sensitivity, warmth, positive affect, and affectionate touch. Oxytocin receptor gene (OXTR) polymorphisms are associated with circulating oxytocin levels, altered brain activity, and parenting behaviors. This study aimed to replicate prior work on OXTR single-nucleotide polymorphisms (SNPs) rs1042778 and rs53576 in relation to maternal sensitivity, explore associations with other aspects of parenting (i.e., negative parenting), evaluate observational and self-report measures of parenting in relation to OXTR SNPs, and examine whether childhood trauma exposure moderates the relation between OXTR SNPs and parenting. Mothers (N = 100) were observed during 2 teaching interaction tasks with their 7-month-old infant, completed questionnaire and interview measures related to parenting and trauma history, and provided saliva specimens to derive OXTR genotypes. Mothers with OXTR rs1042778 TT genotypes demonstrated lower behavioral sensitivity, lower engagement, higher intrusiveness, and more frequent frightened/frightening behavior than mothers with TG or GG genotypes. Genotype interacted with childhood trauma history such that mothers who had experienced childhood trauma were more likely to demonstrate frightened/frightening behavior if they had the TT genotype on rs1042778 relative to the TG or GG genotype; however, small cell sizes for this interaction suggest replication is warranted. Contrary to expectations, mothers with the TT genotype on rs1042778 self-reported that they had less impaired bonding than mothers with TG or GG genotypes. Results are discussed with respect to prior work with oxytocin in lower versus higher risk samples, and the potential role of mothers' self-awareness in explaining discrepancies between results from observational versus self-report measures of parenting.