Gray Joshua C, Sanchez-Roige Sandra, de Wit Harriet, MacKillop James, Palmer Abraham A
Department of Medical and Clinical Psychology, Uniformed Services University, 4301 Jones Bridge Rd., Bethesda, MD, 20814, USA.
Department of Psychiatry, University of California San Diego, 9500 Gilman Dr., La Jolla, CA 92093, USA.
Behav Processes. 2019 May;162:157-161. doi: 10.1016/j.beproc.2019.03.006. Epub 2019 Mar 12.
Delayed reward discounting (DRD) is a behavioral economic measure of impulsivity, reflecting how rapidly a reward loses value based on its temporal distance. In humans, more impulsive DRD is associated with susceptibility to a number of psychiatric diseases (e.g., addiction, ADHD), health outcomes (e.g., obesity), and lifetime outcomes (e.g., educational attainment). Although the determinants of DRD are both genetic and environmental, this review focuses on its genetic basis. Both rodent studies using inbred strains and human twin studies indicate that DRD is moderately heritable, a conclusion that was further supported by a recent human genome-wide association study (GWAS) that used single nucleotide polymorphisms (SNP) to estimate heritability. The GWAS of DRD also identified genetic correlations with psychiatric diagnoses, health outcomes, and measures of cognitive performance. Future research priorities include rodent studies probing putative genetic mechanisms of DRD and human GWASs using larger samples and non-European cohorts. Continuing to characterize genomic influences on DRD has the potential to yield important biological insights with implications for a variety of medically and socially important outcomes.
延迟奖励折扣（DRD）是一种衡量冲动性的行为经济学指标，反映了奖励基于其时间距离而贬值的速度。在人类中，更冲动的DRD与多种精神疾病（如成瘾、注意力缺陷多动障碍）、健康结果（如肥胖）以及终生结果（如教育程度）的易感性相关。尽管DRD的决定因素既有遗传因素也有环境因素，但本综述聚焦于其遗传基础。使用近交系的啮齿动物研究和人类双胞胎研究均表明DRD具有中等程度的遗传性，这一结论得到了最近一项人类全基因组关联研究（GWAS）的进一步支持，该研究使用单核苷酸多态性（SNP）来估计遗传性。DRD的GWAS还确定了与精神疾病诊断、健康结果以及认知表现指标的遗传相关性。未来的研究重点包括探究DRD假定遗传机制的啮齿动物研究，以及使用更大样本和非欧洲队列的人类GWAS。继续刻画基因组对DRD的影响有可能产生重要的生物学见解，对各种医学和社会重要结果具有启示意义。
