Department of Mental Health and Substance Abuse Services, National Institute for Health and Welfare, Helsinki, Finland.
Behav Genet. 2012 Jul;42(4):614-25. doi: 10.1007/s10519-012-9528-z. Epub 2012 Feb 18.
We investigated genetic and environmental influences common to adolescent externalizing behavior (at age 12), smoking (at age 14) and initiation of drug use (at age 17) using the FinnTwin12 cohort data. Multivariate Cholesky models were fit to data from 737 monozygotic and 722 dizygotic twin pairs. Heritability of externalizing behavior was 56%, that of smoking initiation/amount 20/32%, and initiation of drug use 27%. In the best-fitting model common environmental influences explained most of the covariance between externalizing behavior and smoking initiation (69%) and amount (77%). Covariance between smoking initiation/amount and drug use was due to additive genetic (42/22%) and common environmental (58/78%) influences. Half of the covariance between externalizing behavior and drug use was due to shared genetic and half due to the environments shared by co-twins. Using a longitudinal, prospective design, our results indicate that early observed externalizing behavior provides significant underlying genetic and environmental influences common to later substance use, here manifested as initiation of drug use in late adolescence.
我们使用 FinnTwin12 队列数据研究了青少年外化行为（12 岁）、吸烟（14 岁）和药物使用开始（17 岁）共有的遗传和环境影响。多变量 Cholesky 模型适用于 737 对同卵双胞胎和 722 对异卵双胞胎的数据。外化行为的遗传率为 56%，吸烟开始/数量的遗传率为 20/32%，药物使用开始的遗传率为 27%。在拟合最好的模型中，共同环境影响解释了外化行为和吸烟开始（69%）和数量（77%）之间大部分的协方差。吸烟开始/数量和药物使用之间的协方差归因于加性遗传（42%/22%）和共同环境（58%/78%）影响。外化行为和药物使用之间一半的协方差归因于共同的遗传因素，另一半归因于双胞胎共享的环境因素。使用纵向、前瞻性设计，我们的结果表明，早期观察到的外化行为提供了对后来物质使用的重要潜在遗传和环境影响，在这里表现为青少年后期开始使用药物。
