Three genes were predicted to be differently expressed in ADHD + DBDs cases compared with controls after Bonferroni correction (correcting for the total number of tests performed (43,142); P < 1.16 × 10−6); RRM1 (chromosome 11) was less expressed in cases, while RAB3C (chromosome 5) and LEPRE1 (chromosome 1) showed a higher expression in cases when compared to controls (Supplementary Data 5). This evidence concerns the gene RRM1 and attention deficit-hyperactivity disorder.