Can Your DNA Influence Your Bet-Placing? The Impact of Cannabinoid Receptor 1 Gene on Gambling Tasks

Are we placing a bet by ourselves or has our DNA already made the decision for us? Previous research has suggested that some genes related to dopamine or serotonin can influence our non-bet-placing decision-making, but little is known about whether cannabinoid-related genes can impact how much people bet. To investigate this issue, we focused on rs1049353, a single-nucleotide polymorphism of the cannabinoid receptor 1 (CNR1), because it is related to addictive behavior and reward processing. In this study (N = 377), we used a modified Cambridge gambling task to test the effect of rs1049353 polymorphism on how much people bet. We found that participants who are homozygous for C allele placed significantly larger bets than C/T carriers [F(1,371) = 7.805, P = 0.005]. We further studied the gene expression map in human brains and found that the CNR1 gene is overexpressed in striatum, amygdala, and hippocampus. These brain structures are known to underpin reward and risk processing. Our findings suggest that, to some extent, high-level social decision-making even like bet-placing could be influenced by a single genetic locus variation in healthy volunteers. In addition, such effects were likely to be mediated by key brain regions in the reward- and risk-processing networks.