We hypothesized that intranasal oxytocin administration early posttrauma could reduce PTSD risk by attenuating amygdala hyperreactivity to fearful stimuli and by enhancing amygdala-centred functional connectivity of emotion regulation networks (i.e. amygdala-ventral PFC functional connectivity), especially in response to trauma-related stimuli. The gene discussed is OXT; the disease is post-traumatic stress disorder.