stress and behavioral disinhibition in the presence of significant stress whereas modest early life stress exposure is beneficial to all genotypes (the crossover point of graphs in Figure 1, B1 and B2). Childhood inhibited and disinhibited behaviors both predict psychopathology in young adulthood (Caspi et al, 1996). However, the SDQ hyperactivity scores are not diagnostic of pathology per se and therefore the terms behavioral ‘inhibition’ and ‘disinhibition’ may be inappropriate descriptors in our study. Nevertheless, similar G × E crossover effects have been reported in three community studies of boys with longitudinal measures of maltreatment (Caspi et al, 2002; Foley et al, 2004; Kim-Cohen et al, 2006). Although our results are in line with earlier findings, it should be noted that apparently significant G×E interactions can actually be statistical artifacts (Eaves, 2006).
