Catechol-O-Methyltransferase Gene Polymorphisms in Specific Obsessive-Compulsive Disorder Patients' Subgroups

Pharmacological data and animal models support the hypothesis that the dopaminergic (DA) system is implicated in obsessive-compulsive disorder (OCD). Therefore, this case-control study assessed whether genetics variations in catechol-O-methyltransferase gene (COMT) could influence susceptibility to OCD and OCD features in a Brazilian sample. A sample of 199 patients with OCD and 200 healthy individuals was genotyped for -287A > G (rs2075507) and Val158Met (rs4680) single nucleotide polymorphisms (SNPs) by TaqMan(®) or restriction mapping. We observed a statistically significant predominance of the Met low-activity allele in the male patient group as compared to the male healthy control group. The -287A > G polymorphism's genotypes and alleles were significantly overrepresented among male individuals with ordering and female subjects with washing symptoms. We also found female hoarders to exhibit a significant higher frequency of the low activity Met/Met genotype of Val158Met polymorphism compared to female patients who did not express this dimension. Our data suggest an influence of COMT polymorphisms on OCD and OCD patients' features, such as gender, and ordering, washing, and hoarding symptom dimensions. Further studies to confirm the clinical importance of COMT SNPs in OCD are warranted.