THURSDAY, Oct. 23, 2003 (HealthDayNews) -- A new model that looks at genes and environment to identify depression and anxiety in young girls has been developed by researchers at Virginia Commonwealth University (VCU).
The method could help better identify young girls who are at high risk for depression once they enter puberty and begin early intervention. It is outlined in a special October issue of the Journal of Child Psychology and Psychiatry.
This is the first model that simultaneously considers three ways that genes linked to anxiety in young girls influence depression when the girls reach puberty:
- Genes that influence anxiety at a young age increase the liability of a child for developing later depression.
- Girls at genetically high risk for anxiety are exposed disproportionately to adverse life events, such as bad grades or parents' divorce.
- Girls with a higher genetic liability and exposure to adverse life events are more sensitive than other girls to the damaging effects of their environment.
"Genes do play a role in determining why one person gets depression and one person doesn't, but the direct effect of the genes isn't that large," Judy L. Silberg, an associate professor of human genetics and a researcher at VCU's Virginia Institute for Psychiatric and Behavioral Genetics, says in a prepared statement.
"Finding the genes is important, but it is not the only positive contribution that genetically informative studies can make in understanding the mechanisms underlying behavioral development. Genes explain about 30 percent of the difference in people. There are more complicated mechanisms at work."
Silberg says she and her colleagues found genetic factors have different effects at different stages of a person's development.
"A common set of genes can first manifest as anxiety in little girls. When those girls enter puberty, that anxiety can turn into depression. Moreover, the same genes that affect early anxiety increase the girl's risk to exposure to depressing environments, and, moreover, how sensitive they will be to those environments," Silberg says.
"Girls with a genetic liability to anxiety in middle childhood are, therefore, subject to a 'triple hit,' greatly increasing their risk to depression in adolescence."
Here's where you can learn more about depression.