title: Symptoms of attention-deficit/hyperactivity disorder in Down syndrome: effects of the dopamine receptor D4 gene.
abstract: This study examined individual differences in ADHD symptoms and executive function (EF) in children with Down syndrome (DS) in relation to the dopamine receptor D4 (DRD4) gene, a gene often linked to ADHD in people without DS. Participants included 68 individuals with DS (7-21 years), assessed through laboratory tasks, caregiver reports, and experimenter ratings. Saliva samples were collected from the DS group and 66 children without DS to compare DRD4 allele distribution, showing no difference between the groups. When the sample with DS was stratified for ethnicity (n  =  32), the DRD4 7-repeat allele significantly related to parent and experimenter ratings, but not to laboratory assessments. These results suggest that nontrisomy genetic factors may contribute to individual differences in ADHD symptoms in persons with DS.
authors.forename: Gina Marie
authors.initials: GM
authors.lastname: Mason
authors.forename: Goffredina
authors.initials: G
authors.lastname: Spanó
authors.forename: Jamie
authors.initials: J
authors.lastname: Edgin
mesh_terms: D000293:Adolescent; D000328:Adult; D001289:Attention Deficit Disorder with Hyperactivity / Q000453:epidemiology / Q000208:ethnology / Q000235:genetics* / Q000503:physiopathology; D002648:Child; D015897:Comorbidity; D004314:Down Syndrome / Q000453:epidemiology / Q000208:ethnology / Q000235:genetics* / Q000503:physiopathology; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D050638:Receptors, Dopamine D4 / Q000235:genetics*; D055815:Young Adult
chemical_list: C493599:DRD4 protein, human; D050638:Receptors, Dopamine D4
keywords: Down syndrome; Trisomy 21; attention-deficit/hyperactivity disorder; cognitive assessment; dopamine; executive function; intellectual disabilities