title: Attention-deficit/hyperactivity disorder (ADHD) association with the DAT1 core promoter -67 T allele.
abstract: Association between attention deficit hyperactivity disorder (ADHD) and the 10-repeat allele of a polymorphism (a 40 bp variable number of tandem repeats) in the dopamine transporter gene (DAT1) has been reported by several groups. In this study, we examined whether either allele of the DAT1 core promoter -67 functional polymorphism is associated with ADHD in a case/control study. The allele and genotype frequencies of the polymorphism were studied in 110 patients and 120 controls, which were matched on the basis of sex, age and ethnicity. The genotype frequencies in the patients group were as follows: AA 19.2%; AT 65.2%; TT 15.4% vs. the genotype frequencies in the control group: AA 47.5%; AT 43.3%; TT 9.2% [chi2=20.73, df=2, P<or=0.0001]. The T allele of the -67A/T polymorphism revealed an approximately 1.56-fold excess in the patients group comparing with the controls [chi2=14.50, df=1 (P<or=0.001). For the first time, these findings provide tentative evidence of the contribution of the DAT1 gene core promoter polymorphism to the etiopathophysiology of ADHD at least in the Iranian population that we have studied. Further work is warranted to confirm this finding and to assess its generalization to other ethnic groups.
authors.affiliation: Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Evin, and Department of Psychiatry, Rozbeh Hospital, Tehran, Iran. mohadi@uswr.ac.ir
authors.forename: Mina
authors.initials: M
authors.lastname: Ohadi
authors.forename: Elham
authors.initials: E
authors.lastname: Shirazi
authors.forename: Mehdi
authors.initials: M
authors.lastname: Tehranidoosti
authors.forename: Narges
authors.initials: N
authors.lastname: Moghimi
authors.forename: Mohammad R
authors.initials: MR
authors.lastname: Keikhaee
authors.forename: Sima
authors.initials: S
authors.lastname: Ehssani
authors.forename: Ali
authors.initials: A
authors.lastname: Aghajani
authors.forename: Hossein
authors.initials: H
authors.lastname: Najmabadi
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000235:genetics*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D050483:Dopamine Plasma Membrane Transport Proteins / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D006801:Humans; D015810:Linkage Disequilibrium; D008297:Male; D018598:Minisatellite Repeats; D011110:Polymorphism, Genetic / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; C493214:SLC6A3 protein, human