Abstract Parents with substance misuse provide their children with a potentially risky rearing environment. According to the evolutionary life history theory, such environments steer individuals towards faster reproductive strategy. However, parents providing their children with hazardous environments may also pass on genes associated with early parenthood. In register data on individuals born in Sweden 1973–1993 (N = 2,176,128), the hazard ratio of entering parenthood by age 25 was 1.70 (95% CI 1.69–1.72) and 1.85 (1.82–1.89) among offspring of fathers and mothers with substance misuse, respectively, compared to others. In analyses using an offspring-of-siblings design in three types of parental sibling pairs (half siblings, full siblings and dizygotic twins, and monozygotic twins) increasingly controlling for genetic confounding, associations between parental substance misuse and offspring's early reproduction gradually attenuated. Our results suggest that the association between parental substance misuse and earlier parenthood in offspring is at least partly genetically confounded. Life history theory should be further tested with genetically informative research designs.

中文翻译：

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父母物质滥用和后代的生殖时机：一项遗传学研究

摘要 滥用药物的父母为他们的孩子提供了一个潜在危险的抚养环境。根据进化生命史理论，这样的环境引导个体采取更快的繁殖策略。然而，为孩子提供危险环境的父母也可能传递与早期父母身份相关的基因。在 1973-1993 年出生于瑞典的个人的登记数据中（N = 2,176,128），在父亲和母亲的后代中，到 25 岁成为父母的风险比为 1.70（95% CI 1.69-1.72）和 1.85（1.82-1.89）物质滥用，分别与其他人相比。在对三种类型的父母兄弟姐妹（半兄弟姐妹、全兄弟姐妹和异卵双胞胎，以及同卵双胞胎）中使用兄弟姐妹后代设计的分析中，越来越控制遗传混杂，父母物质滥用与后代早期繁殖之间的关联逐渐减弱。我们的研究结果表明，父母物质滥用与后代早期父母身份之间的关联至少在一定程度上是遗传混淆的。生活史理论应进一步检验与遗传信息研究设计。