Sexually dimorphic effects of oxytocin receptor gene (OXTR ) variants on Harm Avoidance

Background Recent research has suggested that oxytocin receptor gene (OXTR) variants may account for individual differences in social behavior, the effects of stress and parenting styles. Little is known, however, on a putative role of the gene in heritable temperamental traits. Methods We addressed effects of two common OXTR variants, rs237900 and rs237902, on personality dimensions in 99 healthy subjects using the Temperament and Character Inventory. Results When sex was controlled for and an OXTR genotype*sex interaction term was included in the regression model, 11% of the variance in Harm Avoidance could be explained (uncorrected p ≤ 0.01). Female carriers of the minor alleles scored highest, and a novel A217T mutation emerged in the most harm avoidant male participant. Conclusions Findings lend support to a modulatory effect of common OXTR variants on Harm Avoidance in healthy caucasian women and invite resequencing of the gene in anxiety phenotypes to identify more explanatory functional variation.