The GABA(A)-receptor γ2 (GABRG2) gene in obsessive-compulsive disorder.
OBJECTIVE
The γ-aminobutyric acid type A (GABA(A)) system may be implicated in obsessive-compulsive disorder, based on its major role in modulation of anxiety and its function as the principal inhibitory neurotransmitter system in the cortex. In addition, glutamatergic/GABAergic mechanisms appear to play a role in the pathophysiology of obsessive-compulsive disorder, making the GABA(A) receptor-γ2 (GABργ2) gene a good candidate for susceptibility in this disorder.


METHODS
118 probands meeting DSM-IV criteria for primary obsessive-compulsive disorder and their available parents were recruited for participation in this study and informed consent was obtained. An NciI restriction site polymorphism in the second intron was genotyped and data was analyzed using the Transmission Disequilibrium Test.


RESULTS
In total, 61 of the participating families were informative (i.e., with at least one heterozygous parent). No biases were observed in the transmission of either of the two alleles (chi² = 0.016, 1 d.f., p = 0.898) to the affected probands in the total sample.


CONCLUSIONS
While these results do not provide support for a major role for the GABA(A) receptor-γ2 in obsessive-compulsive disorder, further investigations of this gene in larger samples are warranted.
Richter
Margaret A
MA
Department of Psychiatry, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada. peggy.richter@sunnybrook.ca
Zai
Gwyneth
G
McBride
Joanna C
JC
Mundo
Emanuela
E
Swinson
Richard P
RP
Kennedy
James L
JL
D000328:Adult; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D015810:Linkage Disequilibrium; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000235:genetics*; D011110:Polymorphism, Genetic; D011963:Receptors, GABA-A / Q000235:genetics*
C546279:GABRG2 protein, human; D011963:Receptors, GABA-A