George S. Zubenko, M.D., Ph.D., professor of psychiatry at the University of Pittsburgh School of Medicine and adjunct professor of biological sciences at Carnegie Mellon University and his team have located a number of chromosomal regions they say hold the genetic keys to a variety of mental illnesses, including major depression and certain addictions. The survey was done in 81 families identified by individuals with recurrent, early-onset, major depressive disorder (RE-MDD), a severe form of depression that runs in families. The Pitt team's findings are published today in the American Journal of Medical Genetics.
Finding the genetic roots of depression is important for many reasons. Depression is the second-leading cause of disability worldwide, affecting nearly 10 percent of the population. And while scientists have made significant progress developing new drugs to treat it, studies that identify specific risk genes may lead to even more effective drugs designed to target depression in specific individuals.
Twin studies have demonstrated that genetic factors typically account for 40 to 70 percent of the risk for developing major depression, but finding those genes has proven to be a challenge because, as in most diseases, there are likely numerous genes involved and only individuals with certain combinations of those genes develop the disorder.
Of equal interest is a secondary finding that longevity in the families who carry these genes is significantly reduced.
The survey revealed 19 loci small regions on chromosomes where genes reside that appear to influence susceptibility to depressive disorders. The results extended the investigators' previous finding that a small region of chromosome 2q containing the
Contact: Craig Dunhoff
University of Pittsburgh Medical Center