D'Onofrio Brian M, Turkheimer Eric, Emery Robert E, Maes Hermine H, Silberg Judy, Eaves Lindon J
Department of Psychological and Brain Sciences, Indiana University 47405, USA.
J Child Psychol Psychiatry. 2007 Jul;48(7):667-75. doi: 10.1111/j.1469-7610.2007.01741.x.
Although parental divorce is associated with increased substance use and internalizing problems, experiencing the separation of one's parents may not cause these outcomes. The relations may be due to genetic or environmental selection factors, characteristics that lead to both marital separation and offspring functioning.
We used the Children of Twins (CoT) Design to explore whether unmeasured genetic or environmental factors related to the twin parent, and measured characteristics of both parents, account for the association between parental divorce and offspring substance use and internalizing problems.
The association between parental divorce and offspring substance use problems remained robust when controlling for genetic and environmental risk from the twin parent associated with parental divorce, and measured characteristics of both parents. The results do not prove, but are consistent with, a causal connection. In contrast, the analyses suggest that shared genetic liability in parents and their offspring accounts for the increased risk of internalizing problems in adult offspring from divorced families.
The study illustrates that unmeasured genetic and environmental selection factors must be considered when studying parental divorce. In explaining associations between parental divorce and young-adult adjustment, our evidence suggests that selection versus causal mechanisms may operate differently for substance abuse (a causal relation) and internalizing problems (an artifact of selection). The CoT design only controls for the genetic and environmental characteristics of one parent; thus, additional genetically informed analyses are needed.
尽管父母离异与物质使用增加及内化问题有关，但经历父母分居未必会导致这些结果。这种关系可能归因于基因或环境选择因素，即那些导致婚姻分居和子女机能的特征。
我们采用双胞胎子女设计来探究与双胞胎父母相关的未测量基因或环境因素，以及父母双方的测量特征，是否能解释父母离异与子女物质使用及内化问题之间的关联。
在控制与父母离异相关的双胞胎父母的基因和环境风险以及父母双方的测量特征后，父母离异与子女物质使用问题之间的关联依然显著。结果虽未证明，但与因果关系相符。相比之下，分析表明父母及其子女共有的基因易感性是导致离异家庭成年子女内化问题风险增加的原因。
该研究表明，在研究父母离异时必须考虑未测量的基因和环境选择因素。在解释父母离异与青年适应之间的关联时，我们的证据表明，选择机制与因果机制在物质滥用（因果关系）和内化问题（选择假象）方面的作用方式可能不同。双胞胎子女设计仅控制了一方父母的基因和环境特征；因此，需要进行更多基于基因信息的分析。
