Dopaminergic and serotonergic genetic variants predict actions and expectations of cooperation and punishment

Genetic variants in dopaminergic and serotonergic pathways have been linked to individual differences in social behavior. In this study, we investigated the relationship between eight allelic variants within these pathways and both behavior and beliefs in 99 participants playing an online Public Goods Game (PGG) with and without punishment. Our results show that individuals with the 5-HTTLPR L/L genotype contributed less and had lower expectations of others’ contributions in the absence of punishment; the 5-HTR1B-rs13212041 T/T genotype was associated with lower expectations of antisocial and spiteful punishment; the COMT-rs4680 A/A (Met/Met) genotype was linked to lower expectations of contributions in the presence of punishment. These findings suggest that specific alleles modulate both cooperative behavior and social expectations, suggesting a genetic contribution to individual variability in responses to social dilemmas.