This is another study about oxytocin role in autism. It reflects a view of autism as mainly about communication skills. Yet autism's diagnostic is not standardized, and as for some other diseases biomarkers are actively seeked as hopes for a genetic origin have been dashed.
Oxytocin (OT), the brain's most abundant neuropeptide, plays an important role in social salience and motivation. Studies have looked at oxytocin's role in various behaviors, including orgasm, social recognition, pair bonding, anxiety, in-group bias, autism, and maternal behaviors.
As Oxytocin is believed to have a significant role in social learning, it has been implicated in the etiology of autism, with one report suggesting autism is correlated to a mutation on the oxytocin receptor gene (OXTR). Low levels of oxytocin could become a new biomarker for individuals that fall into the Autism Spectrum.
Yet clinical trials of the efficacy of oxytocin in autism spectrum disorder (ASD) have reported mixed results due in part to autism spectrum disorder complex etiology. The scientists here hypothesized that genetic and epigenetic variation contribute to variable endogenous oxytocin levels that modulate sensitivity to oxytocin therapy.
To test this hypothesis, the authors integrated genome-wide profiles of DNA-methylation, transcriptional activity, and genetic variation with plasma oxytocin levels in 290 participants with autism spectrum disorder enrolled in a randomized controlled trial of oxytocin.
Their analysis shows subtle, but statistically significant association of plasma oxytocin levels with peripheral transcriptional activity and DNA-methylation profiles across several annotated gene sets. The scientists also identified genetic variants with novel association with plasma oxytocin, several of which reside in known autism spectrum disorder risk genes.
These findings broaden authors' understanding of the effects of the peripheral oxytocin system and provide novel genetic candidates for future studies to decode the complex etiology of autism spectrum disorder and its interaction with oxytocin signaling and oxytocin-based interventions.