Behavioural Genetics Group, MRC Centre for Neuropsychiatric Genetics and Genomics, Neuroscience and Mental Health Research Institute, Cardiff University, Cardiff, UK.
Department of Biology and Biochemistry, University of Bath, Bath, UK.
Genes Brain Behav. 2020 Sep;19(7):e12679. doi: 10.1111/gbb.12679. Epub 2020 Jun 22.
The imprinted genes Grb10 and Nesp influence impulsive behavior on a delay discounting task in an opposite manner. A recently developed theory suggests that this pattern of behavior may be representative of predicted effects of imprinted genes on tolerance to risk. Here we examine whether mice lacking paternal expression of Grb10 show abnormal behavior across a number of measures indicative of risk-taking. Although Grb10 mice show no difference from wild type (WT) littermates in their willingness to explore a novel environment, their behavior on an explicit test of risk-taking, namely the Predator Odor Risk-Taking task, is indicative of an increased willingness to take risks. Follow-up tests suggest that this risk-taking is not simply because of a general decrease in fear, or a general increase in motivation for a food reward, but reflects a change in the trade-off between cost and reward. These data, coupled with previous work on the impulsive behavior of Grb10 mice in the delayed reinforcement task, and taken together with our work on mice lacking maternal Nesp, suggest that maternally and paternally expressed imprinted genes oppositely influence risk-taking behavior as predicted.
印记基因 Grb10 和 Nesp 以相反的方式影响延迟折扣任务中的冲动行为。最近提出的一种理论表明，这种行为模式可能代表了印记基因对风险容忍度的预期影响。在这里，我们研究了缺乏父源表达的 Grb10 的小鼠是否在一系列表明冒险倾向的指标上表现出异常行为。尽管 Grb10 小鼠在探索新环境的意愿上与野生型（WT）同窝仔没有区别，但它们在明确的冒险行为测试，即捕食者气味风险任务中的行为表明它们更愿意冒险。后续测试表明，这种冒险行为不是因为一般的恐惧减少，也不是因为对食物奖励的一般动机增加，而是反映了成本和奖励之间的权衡发生了变化。这些数据，加上之前关于 Grb10 小鼠在延迟强化任务中的冲动行为的研究，以及我们关于缺乏母源 Nesp 的小鼠的研究表明，母源和父源表达的印记基因如预测的那样，对冒险行为产生相反的影响。
