Genetic and Environmental Influences in Delinquent Peer Affiliation: From the Peer Network Approach

Mainstream criminologists have long maintained that delinquent peer group formation is largely a function of family-environmental variables, and have ignored self-selection into peer groups because of genetic proclivities. A small number of recent studies, however, suggest that genes are implicated in delinquent peer affiliation. Given the potentially far-reaching implication of such research findings, the authors replicate Beaver, Wright, & DeLisi‘s (2008) study, among others, using a direct measure of peer delinquency. That is, the authors analyze the Add Health genetic data employing a measure of peer delinquency which is based on the delinquency counts reported by peers themselves rather than respondents‘ self-reports. Even employing this alternative measure, their results clearly support the original study, providing further evidence of genetic underpinnings of delinquent peer group formation. Key Word: biosocial criminology, gene environment interaction, gene environment correlation, delinquent peers Criminology has been largely dominated by sociological paradigms during the better part of the twentieth century. The typical criminologist underscores the saliency of sociological factors as the primary independent variables, while being less likely to entertain the possibility that biological factors may also be responsible for the creation of criminal and delinquent behavior (Moffitt, 2005; Walsh, 2009). Contemporary criminologists are trained more than likely in the sociological paradigm (Cooper, Walsh, & Ellis, 2010) that emphasize such concepts as social learning, subcultures, bonding, socialization, and poverty, and thus tend to de-emphasize theories that contain propositions about genes, neurotransmitters, and hormones. However, great strides have been made in the realm of the biological sciences in recent decades in unraveling causes of human behaviors. This progress has been so remarkable that it led Robinson to point out in a somewhat argumentative manner that: ―The biological sciences have made more progress in advancing our understanding about behavior in the last 10 years than sociology has made in the past 50 years‖ (2004, p. 4). Although such a seemingly adversarial stance such as Robinson‘s does not seem desirable in advancing science, findings from behavioral genetics, molecular genetics, and neuroscience studies have indeed converged to demonstrate that all types of human behavior, including crime and delinquency, are at least partially influenced by genetic factors (Moffitt, 2005; Scarr & McCartney, 1983; Shanahan & Hofer, 2005). In recent years, the field of criminology has witnessed an emergence of a small group of researchers, who actively incorporate biological sciences into criminology. These researchers are advancing the biosocial paradigm to the forefront of the discipline (Cullen, 2009; Walsh, 2009). Their works touch on a variety of correlates of crime and delinquency that have been examined by sociology-based criminologists, including childhood abuse, parental bonding, low self-control, drug and alcohol abuse, gang membership, victimization, and even delinquent peer association (Beaver, Delisi, Vaughn, & Barnes, 2009; Vaughn et al,