FGF1 and attention deficit-hyperactivity disorder: Here, we found that variants DRDR4-rs916457, FGF1-rs2282794 and ADGRL3-rs1565902 are associated with ADHD endophenotypes defined by the total digits, arithmetic and analogies, which evaluate working memory components [33,96], as well as incomplete figures and object assembly, which are related to perceptual organization (Table 2).