In recent years, criminological research has observed an increase in studies examining different offending trajectories. Much of this research has been guided by Moffitt's (1993) developmental taxonomy of life-course persistent offenders, adolescence-limited offenders, and abstainers. Moffitt (1993) argued that the etiologies of these different pathways could be traced to several biosocial factors, including perhaps genetic factors. To date, research has failed to address this possibility directly. The current study addressed this gap in the literature by examining the extent to which genetic factors explain variance in different offending patterns. Analysis of sibling pairs (N = 2,284; ages spanned between 11 and 27 years) drawn from the National Longitudinal Study of Adolescent Health (Add Health) revealed that genetic factors contributed significantly to being classified in each of the different offending patterns. Specifically, genetic factors explained between 56 and 70 percent of the variance in being classified as a life-course persistent offender across different coding strategies, 35 percent of the variance in being classified as an adolescence-limited offender, and 56 percent of the variance in being classified as an abstainer. The authors discuss the importance of integrating genetics into future studies examining offending trajectories. (Published Abstract)