Pairwise genetic correlation with ADHD was estimated for 219 phenotypes using LD score regression41,42 (Online Methods, Supplementary Data 1). Fourty-three phenotypes demonstrated significant genetic overlap with ADHD (P < 2.28 × 10−4), including major depressive disorder43, anorexia nervosa44, educational outcomes45–49, obesity-related phenotypes50–55, smoking56–58, reproductive success59, insomnia60, and mortality61 (Figure 3; Supplementary Table 5). In most domains the genetic correlation is supported by GWAS of multiple related phenotypes. For the positive genetic correlation with major depressive disorder (rg = 0.42, P = 7.38 × 10−38), we also observe a positive correlation with depressive symptoms (rg = 0.45, P = 7.00 × 10−19), neuroticism (rg = 0.26, P= 1.02 × 10−8) and a negative correlation with subjective well-being (rg = −0.28, P = 3.73 × 10−9). The positive genetic correlations with ever smoked (rg = 0.48, P= 4.33 × 10−16) and with number of cigarettes smoked (rg = 0.45, P = 1.07 × 10−5) are reinforced by significant positive correlation with lung cancer (rg = 0.39, P= 6.35 × 10−10). Similarly, genetic correlations related to obesity include significant relationships with body mass
