Psychology Department, Western Carolina University, NC 28723, United States.
Addict Behav. 2013 Oct;38(10):2555-62. doi: 10.1016/j.addbeh.2013.05.014. Epub 2013 Jun 6.
The rates of marijuana abuse are steadily increasing in the U.S. Data suggest that comorbid marijuana abuse and depression is associated with worse outcomes than either diagnosis. Genetic studies independently link the DRD4 gene polymorphism to substance use and to internalizing disorders, but no study has examined whether the DRD4 polymorphism is linked to comorbid marijuana use and depression in a population sample. This study examined associations between the DRD4 gene 48bp VNTR polymorphism and comorbidity between marijuana use frequency and depression in a diverse, non-clinical adolescent sample (n=1882; ages 14 to 18) from the National Longitudinal Study of Adolescent Health (Add Health). Multinomial regression analyses indicated that the odds of being comorbid for depressive symptoms and marijuana use are approximately 2.5≥ with the ≥7R/≥7R genotype than youths who carry the <7R/<7R genotype, controlling for the effects of ethnicity, gender, age, violent victimization, and alcohol related problems. Findings provide genetic clues for psychopathology characterized by prominent externalizing and internalizing features.
在美国，大麻滥用的比例正在稳步上升。数据表明，大麻滥用和抑郁症并存与任何一种诊断相比，结果都更差。遗传研究独立地将 DRD4 基因多态性与物质使用和内化障碍联系起来，但没有研究检查过 DRD4 多态性是否与人群样本中大麻使用和抑郁症并存有关。本研究在国家青少年健康纵向研究（Add Health）的一个多样化的非临床青少年样本（n=1882；年龄 14 至 18 岁）中，研究了 DRD4 基因 48bp VNTR 多态性与大麻使用频率和抑郁并存之间的关联。多项回归分析表明，与携带<7R/<7R 基因型的青少年相比，携带≥7R/≥7R 基因型的青少年出现抑郁症状和大麻使用并存的几率约为 2.5 倍，控制了种族、性别、年龄、暴力受害和酒精相关问题的影响。研究结果为以突出的外在和内在特征为特征的精神病理学提供了遗传线索。
