Oxytocin Gene Variants, Prosocial Behaviour And Associated Brain Structure

In my chapter THE APE THAT DOMESTICATED ITSELF I detail a geat deal of research, some of it featuring Andreas Meyer-Lindenburg, which linked variants in serotonin transporter gene and MAO-A to hyper-vigilant or anti-social behaviour in which there were correlated differences between carriers of long variants and short variants of these genes and the strength of coupling, and therefore feedback, between the amygdala and frontal cortex structures in the brain. Here, Meyer-Lindenburg and colleagues continue the tie-up between gene variants, pro-social behaviour and brain structure by looking at oxytocin. Interesting stuff. Here's the abstract:


Abstract

The evolutionarily highly conserved neuropeptide oxytocin is a key mediator of social and emotional behavior in mammals, including humans. A common variant (rs53576) in the oxytocin receptor gene (OXTR) has been implicated in social-behavioral phenotypes, such as maternal sensitivity and empathy, and with neuropsychiatric disorders associated with social impairment, but the intermediate neural mechanisms are unknown. Here, we used multimodal neuroimaging in a large sample of healthy human subjects to identify structural and functional alterations in OXTR risk allele carriers and their link to temperament. Activation and interregional coupling of the amygdala during the processing of emotionally salient social cues was significantly affected by genotype. In addition, evidence for structural alterations in key oxytocinergic regions emerged, particularly in the hypothalamus. These neural characteristics predicted lower levels of reward dependence, specifically in male risk allele carriers. Our findings identify sex-dependent mechanisms impacting the structure and function of hypothalamic-limbic circuits that are of potential clinical and translational significance.