Although there is no report about the association of DLGAP1 with ADHD, as ADHD shares some genetic basis with other psychiatric disorders, and all these disorders were reported to have impaired cognitive function (Ebmeier, Donaghey, & Steele, 2006; Francazio & Flessner, 2015; Pooragha, Kafi, & Sotodeh, 2013; Thoma, Wiebel, & Daum, 2007), it is valuable to explore the association of DLGAP1 with ADHD through the underlying impaired cognitive function. Here, DLGAP1 is linked to attention deficit-hyperactivity disorder.