In a large series of 303 children and adolescents with a mean age of 13.2 years with a primary diagnosis of ADHD and following treatment in a mental health center, the prevalence of having at least one minor dysfunctional allele was 78.8%, with no association between the different variants of the AOC1 gene and gender [15]. The gene discussed is AOC1; the disease is attention deficit-hyperactivity disorder.