Why do some people bounce back from stressful events while other fall into depression?
Genetic factors play a role in the development of depression and other mood disorders. For example, a gene that may be linked to bipolar disorder has been identified and one study showed that a common family gene mutation could predict whether a person will experience clinical depression when faced with traumatic events in his or her life.
Identical twins, for instance, share the same genes. Research shows that when one identical twin has a mood disorder, there is about a 50% chance that the other will develop the same illness at some point in life. One study showed that if one twin developed depression, the other twin also suffered from depression in 46% of identical twins, compared with 20% of fraternal twins (who share half of their genes, like any full siblings).
When Depression Is All in the Family
A recent study reported in the Archives of General Psychiatry showed that children whose parents and grandparents experienced moderate to severe depression are at much greater risk of developing psychiatric problems, such as depression, than those whose parents or grandparents were not affected. In this three-generation study of 161 children, their parents, and their grandparents, nearly 60% of the children whose parents and grandparents both had a history of depression had at least one psychiatric disorder themselves. In particular, anxiety disorders were an early sign of other, more serious psychiatric problems in children from depressed families; the same was true of their parents.
The researchers stressed that family history of depression and its severity and impairment in previous generations should be taken seriously, as it may help identify young people who are at risk of developing depression later in life. In particular, they note that children with two generations of major depression should be identified and considered for treatment if they develop anxiety disorders.
