Depression Genes Differ Between Sexes

March 29, 2002 -- Depression differs in men and women. And new research funded by the National Institute of Mental Health shows that specific genes that contribute to the disease are likely behind this difference between the sexes. These findings could lead to big changes in the way the condition is treated.

"We suspected there were at least a few different genes involved in making women and men susceptible to major depression," says lead author George S. Zubenko, MD, PhD, in a news release. "The results of this study suggest that sex-specific genes for recurrent major depression may actually be the rule rather than the exception." He is professor of psychiatry at the University of Pittsburgh School of Medicine and adjunct professor of biological sciences at Carnegie Mellon University.

Zubenko and colleagues looked at genetic markers from 100 men and women suffering from ongoing bouts of major depression. They all had a form of severe depression that runs in families, strikes fairly early in life, and impairs health and life span. They compared the markers with those from another 100 men and women with no history of depression.

The researchers identified 16 specific regions of DNA that were associated with depression in either the men or the women, but not in both. This suggests that the underlying molecular basis of severe depression differs by sex, says Zubenko. In addition, men and women may differ in how their bodies deal with stress.

The findings may also help explain why symptoms of depression are different in men and women and why they respond differently to various treatments. This study could also explain why men and women differ in how likely they are to develop other psychiatric problems that tend to run in families, such as alcoholism or anxiety disorders.

"Studies such as this one are providing us with a better understanding of the biology of complicated disorders such as major depression, which is unlikely to represent a single disease with a unitary cause," says Zubenko. "Instead, clinical depression is probably more like anemia. Both of these disorders are defined by a collection of [symptoms] that result from different causes in different people. Treatment or prevention efforts are usually most successful when they are aimed at the specific causes of a disorder."

Next, says Zubenko, the team will attempt to identify the specific genes at work. Then, they can use that information to develop better-targeted drugs and perhaps even find a way to prevent major depression from striking susceptible people.