Fig. 3.

Key gap 2: Tracking dynamic DNAm/ADHD associations over the life course. (a) Epigenome-wide association studies. Examples of different longitudinal profiles of ADHD based on what has been reported in the literature, illustrating the large individual heterogeneity in the onset, level, and persistence of ADHD symptoms from early life to adulthood. Of note, there is ongoing debate about the existence of an ‘adult-onset’ ADHD trajectory, which necessitates more research going forward. Furthermore, while it is clear from existing research that longitudinal profiles of ADHD are heterogeneous across individuals, the specific developmental pathways remain hypothetical. (b) Research priorities for future research making use of repeated measures of both DNAm and ADHD symptoms. DNAm DNA methylation, ADHD attention-deficit/hyperactivity disorder