Lack of an association between a dopamine-4 receptor polymorphism and attention-deficit/hyperactivity disorder: genetic and brain morphometric analyses.
Although the etiology of attention-deficit/hyperactivity disorder (ADHD) is likely multifactorial, family, adoption, and twin studies suggest that genetic factors contribute significantly. Polymorphisms of the dopamine 4 receptor (DRD4) affect receptor binding, and one allele with seven tandem repeats in exon 3 (DRD4*7R) has been associated with ADHD. We examined this putative association in 41 children with severe ADHD and 56 healthy controls who were group matched for ethnicity and sex. The frequency of the DRD4*7R allele did not vary by diagnosis (0.220 vs 0.205 in patients and controls, respectively). Behavioral and brain anatomic MRI measures, previously found to discriminate patients from controls, did not differ significantly between subjects having and those lacking a DRD4*7R allele. These data do not support the reported association between DRD4*7R and the behavioral or brain morphometric phenotype associated with ADHD.
Child Psychiatry Branch, National Institute of Mental Health, Bethesda, MD 20892-1600, USA. fxc@helix.nih.gov
F X
FX
Castellanos
E
E
Lau
N
N
Tayebi
P
P
Lee
R E
RE
Long
J N
JN
Giedd
W
W
Sharp
W L
WL
Marsh
J M
JM
Walter
S D
SD
Hamburger
E I
EI
Ginns
J L
JL
Rapoport
E
E
Sidransky
D000483:Alleles; D001289:Attention Deficit Disorder with Hyperactivity / Q000235:genetics* / Q000473:pathology* / Q000523:psychology; D001921:Brain / Q000033:anatomy & histology*; D002648:Child; D002652:Child Behavior; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010290:Parents; D011110:Polymorphism, Genetic; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D050638:Receptors, Dopamine D4; D012016:Reference Values; D012091:Repetitive Sequences, Nucleic Acid; D012574:Schools
C493599:DRD4 protein, human; D017448:Receptors, Dopamine D2; D050638:Receptors, Dopamine D4