Genetic and Environmental Influences on the Development of Callous-Unemotional Traits

Callous-unemotional traits (CU) (e.g., poverty of emotions, lack of guilt) are a well documented temperamental correlate of severe and persistent antisocial behavior in youths. There is a paucity of longitudinal research that explores the development of CU traits and the etiology of these traits. Using over 9000 youths from the Twins Early Development Study (TEDS), a population-based sample of twins from the U.K., we (1) examined the developmental trajectories of CU traits (between ages 7 to 12), (2) examined the degree to which genetic and environmental influences contributed to the developmental trajectories of CU traits, (3) examined early predictors and outcomes associated with different trajectories of CU traits, and (4) investigated the longitudinal association between CU traits and conduct problems. Our findings suggest that trajectories of CU traits are in most cases influenced by genetic factors, and to a lesser degree by non-shared environmental factors. Highest heritability was observed for boys on a stable high trajectory of CU traits, while shared environmental influences appeared to characterize girls on the stable high trajectory. Our findings also suggest that clinical approaches would benefit from an assessment of CU traits given their reliable association with psychopathology.