Divorce and children: Genes at the root of some problems
It's no secret that divorce can be hard on children but explaining why -- while it may be "easy" for the ex-inlaws -- is not so simple. In one of the first studies to examine genetic roots to the children's problems, Indiana University psychology professor Brian D'Onofrio found that some of the answers do, indeed, lie in the genes.
"We really cannot make any assumptions about what causes the problems associated with divorce," said D'Onofrio, an assistant professor in IU Bloomington's Department of Psychological and Brain Sciences. "For certain problems, such as increased rates of conduct problems and alcohol abuse, the actual divorce seems to cause it. But for depression, it looks like a different mechanism is at work."
D'Onofrio and his colleagues examined the offspring of twins to see if a genetic risk shared by the parents and offspring contribute to some of these problems. When comparing the offspring of identical twins, one of whom experienced a divorce and the other whose marriage was intact, the researchers found no difference in the rates of depression in the offspring (25 percent), who are genetically half-siblings because of the shared genetic material of their parents.
D'Onofrio said studies have shown that people with depression are more likely to see their marriages end in divorce. The same genetic risk that caused depression in the parent could be causing depression in the children regardless of whether the parents divorce. When examining the offspring of identical twins, the children whose parents divorced, however, were twice as likely to experience alcohol problems, indicating something about the separation contributed to this problem.
D'Onofrio's findings appear in the July issue of the Journal of Child Psychology and Psychiatry. Co-authors are Eric Turkheimer and Robert E. Emery, professors at the University of Virginia; and Hermine H. Maes, Judy Silberg, and Lindon J. Eaves, professors at the Virginia Institute for Psychiatric and Behavior Genetics, Virginia Commonwealth University.
In the United States, 40 percent to 50 percent of marriages end in divorce. Numerous studies have shown that the children of divorced parents are more susceptible to a variety of problems, including substance abuse, conduct problems such as getting into fights, and problems at school--such as bad grades or dropping out--but little is known about why this occurs.
D'Onofrio, who studies risk factors involving child adjustment and child psychological findings, cautioned that not all children of divorced parents experience these problems. The findings, however, point to a greater need to help families after a divorce.
"It really suggests that either reducing divorce rates or intervening with families after divorce can really decrease alcohol problems and conduct problems," D'Onofrio said.
The study involved 4,800 offspring of 14,763 twins and their spouses.