Polygenic Risk Score Effect on Violent Behavior in Schizophrenia

Previous studies aiming to establish a correlation between schizophrenia (SCZ) and aggressive behavior have resulted in contradictory results. Despite this, a certain degree of evidence suggests a potential underlying genetic component to aggression in SCZ. Polygenic risk score (PRS) analysis is a novel technique to estimate the combined effect of multiple genetic influences on aggression. Our objective was to investigate whether PRS could determine a proclivity toward aggressive behavior in patients with SCZ. Community-dwelling patients diagnosed with a schizophrenia spec-trum disorder (n = 205) were recruited from a nonforensic outpatient sample. Participants were assessed for aggression using a cross-sectional and retrospective design, and PRS was calculated using genomic DNA and the Illumina Omni 2.5 array. We did not detect any associations between lifetime physical aggression (P = .32), verbal aggression (P = .24), or aggression against property (P = .24) and the PRS for SCZ risk. There may be several reasons to explain our null findings. We recommend that future interaction analyses of PRSs in SCZ that investigate violence focus on for-ensic psychiatric patients with higher base rates of violence and use participant interviews to assess aggression.