The biological basis of anger: associations with the gene coding for DARPP-32 (PPP1R1B) and with amygdala volume

Recent findings have highlighted the importance of DARPP-32 (dopamine- and cAMP-regulated phosphoprotein, 32 kDa), a key regulatory molecule in the dopaminergic signalling pathway for dopamine related phenotypes like antisocial-behavior, drug addiction and schizophrenia. This is the first study investigating the role of the DARPP-32 gene for personality. In a sample of n=838 healthy German Caucasian subjects we found a significant association between rs907094 and ANGER. Carriers of the T-allele showed significantly higher ANGER scores than participants without a T-allele (F((1,837))=9.52, p=0.002). In a second step we validated self-report data of ANGER by investigating their relation to structural brain differences in anger-related brain regions using voxel-based morphometry. A negative association between ANGER scores and the volume of the left amygdala could be detected. The present findings yield genetic evidence for the importance of dopaminergic signal transduction for the personality trait of ANGER. In addition volumetric MRI data support the role of the amygdala for the processing of anger.