What Causes Depression? Stress, Serotonin Gene Link Investigated

Researchers at the Washington University School of Medicine in St. Louis recently found that a connection between serotonin and depression, long taken as gospel, does not actually exist. The research disproved a landmark 2003 study, which has since been cited more than 4,000 times, that linked the serotonin gene to inhibited ability to deal with stress and, in turn, a greater likelihood of depression.