Background:

Youth conduct problems (CP; fighting, stealing) are a major public health concern and a key target for prevention and intervention efforts. CP youth often experience high levels of environmental risk (e.g. harsh parenting, family conflict) and psychiatric comorbidity (e.g. depression, ADHD, substance use). Yet, little is known about biological factors that may explain the link between environmental risk, CP and comorbid symptoms.

Aims:

To investigate the role of DNA methylation - an epigenetic mechanism sensitive to environmental influences - in the development of CP and related comorbidities. Specific aims are to: (i) identify methylation markers that are associated with multiple symptoms vs symptom-specific markers; (ii) investigate whether methylation markers cluster to form biologically informative systems; (iii) examine methylation changes in relevant markers over time; (iv) establish whether markers are influenced by pre- and postnatal environmental risk exposure; and (v) test whether methylation mediates environmental effects on CP and comorbidities.