Objective: This study aims to investigate the influence of the COMT Val(108/158)Met polymorphism on trait and behavioural impulsivity in binge eating disorder (BED). COMT Val(108/158)Met has been related to impulsivity in previous studies, but so far no study has investigated the role of this polymorphism in the context of BED.
Method: Impulsivity was assessed via a questionnaire (trait) and on a behavioural level via the antisaccade task in a sample of 69 participants classified into one out of three age-matched groups: (1) obese individuals with BED according to DMS-IV (BED+); (2) obese individuals without BED, matched with the BED+ sample according to body weight (OBED-); and (3) normal-weight healthy controls (NWC). The COMT Val(108/158)Met polymorphism was genotyped in all samples.
Results: As expected, the BED+ sample showed higher trait and behavioural impulsivity. Furthermore, within the BED+ group, COMT Met/Met homozygous individuals showed stronger deficits in inhibitory control.
Discussion: COMT Met/Met homozygous individuals with BED might represent a specific group in the BED spectrum, which shows a higher behavioural impulsivity. The association between COMT Val(108/158)Met with inhibitory control should be interpreted with caution because of the small sample size. Larger replication studies are needed to further elucidate the role of the COMT Val(108/158)Met polymorphism in the regulation of disordered eating behaviour.
Keywords: binge eating disorder; genetics; obesity.
Copyright © 2015 John Wiley & Sons, Ltd and Eating Disorders Association.