Gene Variant Could Predict Chance of Depression

Genetic psychiatrists examine a gene that could affect depressive behavior.

ByABC News
January 3, 2011, 1:02 PM

Jan. 4, 2011— -- Whether you roll with life's punches or become depressed in the face of stress may be determined, in part, by your genes, according to new research from the University of Michigan.

The study, published in the Archives of General Psychiatry Monday, examined evidence from 54 studies that identified a particular gene variant, often referred to as the depression gene, as a possible determinant in who will and who will not suffer from clinical depression.

Although the predictive power of the gene variant was recently called into question by a smaller 2009 meta-analysis of 14 studies, researchers argue that the gene, 5-HTTLPR, does, indeed, affect a patient's chances of developing depression.

"That [2009] meta-analysis has been criticized for many reasons, mostly because they only include a few of the studies out there on this gene," says Dr. Srijan Sen, assistant professor of psychiatry at the University of Michigan Medical School and co-author on the study.

"We did a meta-analysis of all 54 studies that exist and, overall, we found that the results support [the existence of the gene] pretty strongly."

Although Sen says the gene has a relatively small impact on chances of developing depression, perhaps accounting for five 7 percent of one's likelihood, he hopes that the meta-analysis will help fuel the discovery of other genetic variants that influence depression.

Other genetic variants influencing depression have been reported, he says, but 5-HTTLPR is the only one "we can confidently say is real."

With a greater understanding of the genes that predict a predisposition toward depression, clinicians could better tailor treatment and provide supportive treatment to those at risk of developing depression, Sen says, an advancement that he believes is perhaps only a decade away.