Childhood abuse, the BDNF-Val66Met polymorphism and adult psychotic-like experiences

Background: The well-established relationship between childhood adversity and psychosis is likely to involve other factors such as genetic variants that can help us to understand why not everyone exposed to adverse events develops psychotic symptoms later in life. Aims: We investigated the influence of childhood abuse and neglect on positive and negative psychotic-like experiences in adulthood and the potential moderating effect of the BDNF-Val66Met polymorphism. Method: Psychotic-like experiences and childhood adversity were assessed in 533 individuals from the general population. Results: Childhood abuse showed a strong independent effect on the positive dimension of psychotic-like experiences (β = 0.16, s.e. = 0.05, P = 0.002). Furthermore, this association was moderated by the BDNF-Val66Met polymorphism (β = 0.27, s.e. = 0.10, P = 0.004). Conclusions: Individuals exposed to childhood abuse are more likely to report positive psychotic-like experiences. Met carriers reported more positive psychotic-like experiences when exposed to childhood abuse than did individuals carrying the Val/Val genotype. Therefore, the observed gene-environment interaction effect may be partially responsible for individual variation in response to childhood abuse.