To address these gaps in the literature, the current study aims to: 1) identify subtypes of comorbidity among alcohol and marijuana abuse/dependence, nicotine dependence, conduct disorder, anxiety disorder and major depressive disorder in adolescents and young adults using latent class analysis, 2) determine if the familial vulnerability associated with parental SUD and internalizing disorders is associated with subtypes of comorbidity, and 3) identify parenting behaviors, early family environmental factors, and perceived sibling and peer influences that are associated with subtypes of comorbidity after accounting for familial vulnerability in an offspring-of-twins design.
