Research article

Catechol-O-Methyltransferase (COMT) Val^108/158 Met polymorphism does not modulate executive function in children with ADHD

Evan Taerk¹ , Natalie Grizenko¹ , Leila Ben Amor³ , Philippe Lageix¹ , Valentin Mbekou¹ , Rosherie Deguzman¹ , Adam Torkaman-Zehi¹ , Marina Ter Stepanian¹ , Chantal Baron¹ and Ridha Joober^1,2,3

¹  Department of Psychiatry, McGill University and Douglas Hospital Research Centre, Montreal, Quebec, H4H 1R3, Canada

²  Department Neurology and Neurosurgery, McGill University and Douglas Hospital Research Centre, Montreal, Quebec, H4H 1R3, Canada

³  Department of Human Genetics, McGill University and Douglas Hospital Research Centre, Montreal, Quebec, H4H 1R3, Canada

author email corresponding author email

BMC Medical Genetics 2004, 5:30doi:10.1186/1471-2350-5-30

Published:	21 December 2004

Abstract

Background

An association has been observed between the catechol-O-methyltransferase (COMT) gene, the predominant means of catecholamine catabolism within the prefrontal cortex (PFC), and neuropsychological task performance in healthy and schizophrenic adults. Since several of the cognitive functions typically deficient in children with Attention Deficit Hyperactivity Disorder (ADHD) are mediated by prefrontal dopamine (DA) mechanisms, we investigated the relationship between a functional polymorphism of the COMT gene and neuropsychological task performance in these children.

Methods

The Val^108/158 Met polymorphism of the COMT gene was genotyped in 118 children with ADHD (DSM-IV). The Wisconsin Card Sorting Test (WCST), Tower of London (TOL), and Self-Ordered Pointing Task (SOPT) were employed to evaluate executive functions. Neuropsychological task performance was compared across genotype groups using analysis of variance.

Results

ADHD children with the Val/Val, Val/Met and Met/Met genotypes were similar with regard to demographic and clinical characteristics. No genotype effects were observed for WCST standardized perseverative error scores [F_2,97 = 0.67; p > 0.05], TOL standardized scores [F_2,99 = 0.97; p > 0.05], and SOPT error scores [F_2,108 = 0.62; p > 0.05].

Conclusions

Contrary to the observed association between WCST performance and the Val^108/158 Met polymorphism of the COMT gene in both healthy and schizophrenic adults, this polymorphism does not appear to modulate executive functions in children with ADHD.