Childhood emotional environment and self-injurious behaviors: The moderating role of the BDNF Val66Met polymorphism

BackgroundPrevious theory has suggested that invalidating environments in the form of emotional maltreatment should be a specific risk factor for the development of self-injurious behaviors (Linehan, 1993, Cognitive-Behavioral Treatment of Borderline Personality Disorder, New York, Guilford Press). However, results from previous studies have been mixed, possibly indicating that this effect may not be the same for all individuals. In fact, some individuals may be more susceptible to environmental influences (i.e., phenotypic plasticity), and this susceptibility may be in part a function of genes that are involved in neuroplasticity (e.g., the brain-derived neurotrophic factor [BDNF] Val66Met polymorphism).MethodWe explored the interaction between retrospective reports of childhood emotional environment and the BDNF Val66Met polymorphism in relation to a history of two main types of self-injurious behaviors, suicide attempt and nonsuicidal self-injury (NSSI), in a sample of individuals with a history of involvement in the criminal justice system.ResultsFor individuals with two Val alleles, there was a significant direct relationship between emotional maltreatment and self-injurious behaviors. However, the relationship was not significant for Met carriers.LimitationsThe data are cross-sectional, which means causal inferences cannot be drawn.ConclusionsThe results indicate the possibility of a common etiological pathway for NSSI and suicide attempts.