title: Increased prevalence of the seven-repeat variant of the dopamine D4 receptor gene in patients with obsessive-compulsive disorder with tics.
abstract: The polymorphism characterized by a varying number of 48 bp repeats (VNTR) in the dopamine D4 receptor (DRD4) gene was examined in 61 obsessive-compulsive disorder (OCD) probands with and without tics. Most of the OCD patients with tics showed at least one copy of the 7-fold variant compared to those affected subjects without tics (91 vs. 48%, respectively, Yates corrected chi2 = 5.54, P = 0.018). Similarly, a higher number of copies of this common variant were detected in the group of probands displaying tics compared to those OCD's without tics (Yates corrected chi2 = 4.66, P = 0.03). Our study suggests that the seven-repeat allele of the DRD4 gene could be a factor in the phenotypic variance of tics among OCD individuals.
authors.affiliation: Departamento de Genética Psiquiátrica, Instituto Mexicano de Psiquiatría Calzada Mexico-Xochimilco, San Lorenzo Huipulco, Mexico D.F. cruz@cenids.ssa.gob.mx
authors.forename: C
authors.initials: C
authors.lastname: Cruz
authors.forename: B
authors.initials: B
authors.lastname: Camarena
authors.forename: N
authors.initials: N
authors.lastname: King
authors.forename: F
authors.initials: F
authors.lastname: Páez
authors.forename: D
authors.initials: D
authors.lastname: Sidenberg
authors.forename: J R
authors.initials: JR
authors.lastname: de la Fuente
authors.forename: H
authors.initials: H
authors.lastname: Nicolini
mesh_terms: D000483:Alleles; D004247:DNA / Q000032:analysis; D005192:Family Health; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008297:Male; D009771:Obsessive-Compulsive Disorder / Q000235:genetics*; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D050638:Receptors, Dopamine D4; D012091:Repetitive Sequences, Nucleic Acid; D013981:Tic Disorders / Q000235:genetics*; D005879:Tourette Syndrome / Q000235:genetics
chemical_list: C493599:DRD4 protein, human; D017448:Receptors, Dopamine D2; D050638:Receptors, Dopamine D4; D004247:DNA