The effects of COMT (Val108/158Met) and DRD4 (SNP -521) dopamine genotypes on brain activations related to valence and magnitude of rewards.
People's sensitivity to reinforcing stimuli such as monetary gains and losses shows a wide interindividual variation that might in part be determined by genetic differences. Because of the established role of the dopaminergic system in the neural encoding of rewards and negative events, we investigated young healthy volunteers being homozygous for either the Valine or Methionine variant of the catechol-O-methyltransferase (COMT) codon 158 polymorphism as well as homozygous for the C or T variant of the SNP -521 polymorphism of the dopamine D4 receptor. Participants took part in a gambling paradigm featuring unexpectedly high monetary gains and losses in addition to standard gains/losses of expected magnitude while undergoing functional magnetic resonance imaging at 3 T. Valence-related brain activations were seen in the ventral striatum, the anterior cingulate cortex, and the inferior parietal cortex. These activations were modulated by the COMT polymorphism with greater effects for valine/valine participants but not by the D4 receptor polymorphism. By contrast, magnitude-related effects in the anterior insula and the cingulate cortex were modulated by the D4 receptor polymorphism with larger responses for the CC variant. These findings emphasize the differential contribution of genetic variants in the dopaminergic system to various aspects of reward processing.
Camara
Estela
E
Department of Psicologia Basica, Faculty of Psychology, University of Barcelona, 08035 Barcelona, Spain.
Krämer
Ulrike M
UM
Cunillera
Toni
T
Marco-Pallarés
Josep
J
Cucurell
David
D
Nager
Wido
W
Mestres-Missé
Anna
A
Bauer
Peter
P
Schüle
Rebecca
R
Schöls
Ludger
L
Tempelmann
Claus
C
Rodriguez-Fornells
Antoni
A
Münte
Thomas F
TF
D000293:Adolescent; D000328:Adult; D019943:Amino Acid Substitution / Q000235:genetics; D001923:Brain Chemistry / Q000235:genetics*; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D002540:Cerebral Cortex / Q000201:enzymology / Q000378:metabolism; D003342:Corpus Striatum / Q000201:enzymology / Q000378:metabolism; D003596:Cytosine / Q000378:metabolism; D004298:Dopamine / Q000235:genetics*; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D007206:Individuality; D008297:Male; D008715:Methionine / Q000235:genetics; D010296:Parietal Lobe / Q000201:enzymology / Q000378:metabolism; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D050638:Receptors, Dopamine D4 / Q000235:genetics*; D012201:Reward; D012309:Risk-Taking; D015533:Transcriptional Activation / Q000235:genetics; D014633:Valine / Q000235:genetics; D055815:Young Adult
D050638:Receptors, Dopamine D4; D003596:Cytosine; D008715:Methionine; D002394:Catechol O-Methyltransferase; D014633:Valine; D004298:Dopamine