COMT Val158Met polymorphism and executive functions in obsessive-compulsive disorder

Area of Science:

• Neuroscience
• Genetics
• Psychiatry

Background:

• Obsessive-compulsive disorder (OCD) is a neuropsychiatric condition associated with executive function deficits.
• The catechol-O-methyl transferase (COMT) enzyme plays a crucial role in dopamine metabolism within the prefrontal cortex.
• The COMT Val158Met polymorphism influences enzyme activity and dopamine levels, potentially impacting cognitive functions.

Purpose of the Study:

• To investigate the association between the COMT Val158Met polymorphism and executive functions in patients with OCD.
• To compare genotype distributions and executive function performance between OCD patients and healthy controls.

Main Methods:

• A cohort of 101 OCD patients and 100 healthy controls (HS) were genotyped for the COMT Val158Met polymorphism.
• Executive functions were assessed using the Trail Making Test (TMT) B-A difference and lexical fluency tests.

Main Results:

• No significant differences in genotype distributions were observed between the OCD and HS groups.
• OCD patients carrying the Met allele (Met carriers) exhibited significantly poorer performance on the TMT B-A difference and lexical fluency compared to both HS subgroups.

Conclusions:

• The findings suggest that the lower COMT enzyme activity associated with the Met allele may contribute to impaired executive functions in individuals with OCD.
• Elevated prefrontal cortex dopamine levels due to reduced COMT activity could underlie these cognitive deficits in OCD patients.