Association of catechol-o-methyltransferase (COMT) gene rs4680 polymorphism and risk of obsessive-compulsive disorder in a clinically characterized Bangladeshi cohort

Abstract

Background: The catechol-O-methyltransferase (COMT) gene is crucial for breaking down dopamine. The Val158Met polymorphism (rs4680) affects its enzymatic activity. Our study aims to assess the association of the rs4680 (Val158Met) polymorphism in the COMT gene with obsessive-compulsive disorder (OCD) among Bangladeshi population. Methods: We conducted a case-control study with 90 OCD patients and 90 healthy controls, matched by age and gender. The participants had been recruited from the Psychiatry Department of Bangladesh Medical University (BMU), Dhaka. Genomic DNA was isolated from each participant’s blood sample, and the genotyping of the rs4680 polymorphism was investigated utilizing PCR-RFLP analysis. Results: The GA genotype was detected at a significantly greater frequency in OCD patients (38.89%) than in the control group (21.11%) (OR = 2.59, p = 0.005). The A allele also showed a significant association with OCD risk (OR = 2.41, p = 0.002). Female patients demonstrated stronger associations in the GA genotype comparison (OR = 2.89, p = 0.025), dominant model (OR = 3.22, p = 0.010), and A allele comparison (OR = 2.84, p = 0.007), whereas male patients showed no statistically significant associations. Conclusion: The findings of our study suggest that the COMT Val158Met polymorphism may have association with OCD risk in this cohort, with an increased susceptibility found among females. The A allele was also significantly linked to increased OCD risk in females, but not in males. More extensive studies are necessary to explore these observations with larger and more diverse populations. Clinical trial number: Not applicable. © The Author(s) 2026.