Scientists say they have discovered the first solid evidence that variations in some peoples’ genes may cause depression -- one of the world’s most common and costly mental illnesses. And in a rare occurrence in genetic research, a British-led international team’s finding of a DNA region linked to depression has been replicated by another team from the United States who were studying an entirely separate group of people. “What’s remarkable is that both groups found exactly the same region in two separate studies,” Pamela Madden, who led the U.S. team at Washington University, said in a statement.
