Evaluating the genetic susceptibility to peer reported bullying behaviors.

Bullying is a significant public health concern with lasting impacts on youth. Although environmental risk factors for bullying have been well-characterized, genetic influences on bullying are not well understood. This study explored the role of genetics on early childhood bullying behavior. Participants were 561 children who participated in a longitudinal randomized control trial of a preventive intervention beginning in first grade who were present for the first grade peer nominations used to measure early childhood bullying and who provided genetic data during the age 19-21 year follow-up in the form of blood or saliva. Measures included a polygenic risk score (PRS) derived from a conduct disorder genome wide association study. Latent profile analysis identified three profiles of bullying behaviors during early childhood. Results suggest that the PRS was significantly associated with class membership, with individuals in the moderate bully-victim profile having the highest levels of the PRS and those in the high bully-victim profile having the lowest levels. This line of research has important implications for understanding genetic vulnerability to bullying in early childhood.