On the other hand, the replication results from EAGLE30/QIMR92 are much stronger and support the hypothesis that ADHD is the extreme expression of one or more heritable quantitative traits110. We observe strong concordance between the GWAS of ADHD and the previous GWASs of ADHD-related traits in the population, both in terms of genome-wide genetic correlation and concordance at individual loci. Polygenic risk for ADHD has previously been associated with inattentive and hyperactive/impulsive trait variation below clinical thresholds in the population29. Shared genetic risk with health risk behaviors may similarly be hypothesized to reflect an impaired ability to self-regulate and inhibit impulsive behavior111,112. The observed negative correlation between ADHD and anorexia nervosa may also be related to these behavioral factors.
