Confirmation that a specific haplotype of the dopamine transporter gene is associated with combined-type ADHD.
OBJECTIVE
The primary purpose of this study was to confirm the association of a specific haplotype of the dopamine transporter gene and attention deficit hyperactivity disorder (ADHD), which could be one source of the heterogeneity seen across published studies.


METHODS
The authors previously reported the association of ADHD with a subgroup of chromosomes containing specific alleles of two variable-number tandem repeat polymorphisms within the 3' untranslated region and intron 8 of the dopamine transporter gene. They now report on this association in a sample of ADHD combined-type probands.


RESULTS
The original observations were confirmed, with an overall odds ratio of 1.4 across samples.


CONCLUSIONS
These data challenge results of meta-analyses suggesting that dopamine transporter variation does not have an effect on the risk for ADHD, and they indicate that further investigation of functional variation in the gene is required.
Asherson
Philip
P
MRC Social Genetic Developmental and Psychiatry Centre, Institute of Psychiatry, London, SE5 8AF UK. p.asherson@iop.kcl.ac.uk
Brookes
Keeley
K
Franke
Barbara
B
Chen
Wai
W
Gill
Michael
M
Ebstein
Richard P
RP
Buitelaar
Jan
J
Banaschewski
Tobias
T
Sonuga-Barke
Edmund
E
Eisenberg
Jacques
J
Manor
Iris
I
Miranda
Ana
A
Oades
Robert D
RD
Roeyers
Herbert
H
Rothenberger
Aribert
A
Sergeant
Joseph
J
Steinhausen
Hans-Christoph
HC
Faraone
Stephen V
SV
D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D050483:Dopamine Plasma Membrane Transport Proteins / Q000235:genetics*; D005260:Female; D014644:Genetic Variation / Q000235:genetics; D006239:Haplotypes / Q000235:genetics*; D006801:Humans; D008297:Male; D011110:Polymorphism, Genetic; D015203:Reproducibility of Results; D012307:Risk Factors; D020080:Tandem Repeat Sequences
D050483:Dopamine Plasma Membrane Transport Proteins