Center for Cognitive and Decision Sciences, Department of Psychology, University of Basel, Basel, Switzerland.
PLoS One. 2012;7(6):e39135. doi: 10.1371/journal.pone.0039135. Epub 2012 Jun 18.
Twin-studies suggest that a significant portion of individual differences in the propensity to take risks resides in people's genetic make-up and there is evidence that variability in dopaminergic systems relates to individual differences in risky choice. We examined the link between risk taking in a risk taking task (the Balloon Analogue Risk Task, BART) and a variable number tandem repeat (VNTR) polymorphism in the 3'UTR of the dopamine transporter gene (SLC6A3/DAT1). Behavior in BART is known to be associated with activity in striatal reward-processing regions, and DAT1 is assumed to modulate striatal dopamine levels. We find that carriers of DAT1 alleles, which presumably result in lower striatal dopamine availability, showed more risk taking, relative to carriers of the alleles associated with higher striatal dopamine availability. Our analyses suggest that the mechanism underlying this association is diminished sensitivity to rewards among those who take more risks. Overall, our results support the notion that a behavioral genetic approach can be helpful in uncovering the basis of individual differences in risk taking.
双生子研究表明，个体冒险倾向的差异很大程度上存在于人们的基因构成中，有证据表明多巴胺能系统的变异性与冒险选择的个体差异有关。我们研究了冒险任务（气球模拟风险任务，BART）中的冒险行为与多巴胺转运体基因（SLC6A3/DAT1）3'UTR 中的可变数串联重复（VNTR）多态性之间的联系。众所周知，BART 中的行为与纹状体奖励处理区域的活动有关，而 DAT1 被认为调节纹状体多巴胺水平。我们发现，DAT1 等位基因的携带者，据推测会导致纹状体多巴胺的可用性降低，与与纹状体多巴胺可用性较高的等位基因携带者相比，表现出更多的冒险行为。我们的分析表明，这种关联的机制是那些冒险行为更多的人对奖励的敏感性降低。总的来说，我们的结果支持这样一种观点，即行为遗传学方法有助于揭示冒险行为个体差异的基础。
