Association study between obsessive-compulsive disorder and serotonergic candidate genes.
BACKGROUND
To date, research examining the relationship between serotonergic genes and obsessive-compulsive disorder (OCD) has yielded conflicting results. The purpose of this study is to investigate the association between four serotonergic polymorphisms (STin2 VNTR and 5-HTTLPR of the SLC6A4 gene, and A-1438G (rs6311) and T102C (rs6313) of the HTR2A gene) and OCD.


METHODS
99 OCD patients, 456 non-OCD psychiatric patients, and 420 healthy controls from a homogeneous Spanish Caucasian population were genotyped using standard methods.


RESULTS
All groups showed Hardy-Weinberg equilibrium for the analyzed genetic variability. A-1438G and T102C polymorphisms were in complete linkage disequilibrium. OCD patients showed an excess of STin2.12 carriers (12/12, 12/10, and 12/9 genotypes) compared with healthy controls (chi(2) (1)=7.21, corrected p=0.021; OR=3.38, 95% CI=1.32-8.62) and non-OCD psychiatric patients (chi(2) (1)=6.70, corrected p=0.030; OR=3.24, 95% CI=1.27-8.26). However, no differences were found between non-OCD patients and healthy controls (chi(2) (1)=0.05, corrected p>1; OR=1.04, 95% CI=0.72-1.51). No significant differences were found with respect to A-1438G and 5-HTTLPR polymorphisms.


CONCLUSIONS
Our data provide supporting evidence of an association between the STin2 VNTR polymorphism of the SLC6A4 gene and OCD.
Saiz
Pilar A
PA
Department of Psychiatry, School of Medicine, University of Oviedo, Julian Claveria 6-3, 33006 Oviedo, Spain. frank@uniovi.es
Garcia-Portilla
Maria P
MP
Arango
Celso
C
Morales
Blanca
B
Bascaran
Maria-Teresa
MT
Martinez-Barrondo
Sara
S
Florez
Gerardo
G
Sotomayor
Emilio
E
Paredes
Begoña
B
Alvarez
Cesar
C
San Narciso
Gema
G
Carreño
Eduardo
E
Bombin
Igor
I
Alvarez
Victoria
V
Coto
Eliecer
E
Fernandez
Juan M
JM
Bousoño
Manuel
M
Bobes
Julio
J
D000328:Adult; D016009:Chi-Square Distribution; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D015810:Linkage Disequilibrium; D008297:Male; D008875:Middle Aged; D009771:Obsessive-Compulsive Disorder / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D044402:Receptor, Serotonin, 5-HT2A / Q000235:genetics*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*
D044402:Receptor, Serotonin, 5-HT2A; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins