Effects of COMT val158met genoype on brain activity during processing of negative pictures: a replication
Spalek, K.1, Buholzer, S.1, de Quervain, D.2, Papassotiropoulos, A.1, and Rasch, B.1,2
1Division of Molecular Psychology, University of Basel; 2Division of Psychiatry Research, University of Zürich
A functional single nucleotide polymorphism in the catochol-O-methyltransferase gene (COMTval158met) influences the enzymatic activity of COMT, which degrades catecholamines (dopamine, epinephrine and norepinephrine). The low-activity met158 allele has been associated with higher responsivity of limbic brain regions to emotional stimuli and with higher risk for anxiety-related behaviors. We investigated the impact of COMTval158met genotype on brain activity during processing of emotional pictures using functional magnetic resonance imaging (fMRI). 55 healthy subjects viewed pictures taken from the International Affective Picture System (IAPS) in the fMRI scanner. We show that Met/Met homozygotes, exhibit increased brain activity during processing of unpleasant pictures in the amygdala, parahippocampus and prefrontal area as compared to Val carriers. Amygdala activity was positively correlated with the number of met158 alleles. No genotype-dependent differences were observed for pleasant stimuli. Our results replicate the findings of Smolka et al. (2005) and support the notion that COMT genotype affects emotional processing.