title: Dopamine system genes and attention deficit hyperactivity disorder: a meta-analysis.
abstract: The dopamine system may play a major role in the development of attention deficit hyperactivity disorder (ADHD). We applied a random-effects model meta-analysis to family-based studies of association between ADHD and the dopamine system genes DRD4, DRD5 and DAT1. A statistical test of heterogeneity was conducted for each group of studies. The meta-analysis of DRD4 included data from 13 studies, with a total of 571 informative meioses. The pooled odds ratio estimate was 1.41 (95% CI 1.20-1.64, =1.57 x 10 ), demonstrating positive association. For DRD5, data from five studies, with a total of 340 informative meioses, were combined yielding a pooled odds ratio of 1.57 (95% CI 1.25-1.96, =8.28 x 10 ). Eleven studies examining DAT1, with a total of 824 informative meioses, yielded a non-significant pooled odds ratio estimate of 1.27 (95% CI 0.99-1.63, 0.06). There was no support of heterogeneity between the studies. Overall, the meta-analyses support the involvement of the dopamine system genes in ADHD liability variation and suggest the need for studies examining interactions between these genes.
authors.affiliation: Division of Oral Biology, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA. maherb@sdmgenetics.pitt.edu
authors.forename: Brion S
authors.initials: BS
authors.lastname: Maher
authors.forename: Mary L
authors.initials: ML
authors.lastname: Marazita
authors.forename: Robert E
authors.initials: RE
authors.lastname: Ferrell
authors.forename: Michael M
authors.initials: MM
authors.lastname: Vanyukov
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000235:genetics*; D004298:Dopamine / Q000502:physiology*; D050483:Dopamine Plasma Membrane Transport Proteins; D006801:Humans; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins / Q000235:genetics; D009419:Nerve Tissue Proteins; D017447:Receptors, Dopamine D1 / Q000235:genetics; D017448:Receptors, Dopamine D2 / Q000235:genetics; D050638:Receptors, Dopamine D4; D050641:Receptors, Dopamine D5
chemical_list: C493599:DRD4 protein, human; C493605:DRD5 protein, human; D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; C493214:SLC6A3 protein, human; D050638:Receptors, Dopamine D4; D050641:Receptors, Dopamine D5; D004298:Dopamine