In our era of instant gratification, the world of medicine seems like an outlier. The path from a promising discovery to an effective treatment often takes a decade or more…After years of controversy, gene therapy is poised to become a viable option for a variety of often life-threatening medical conditions, especially those resulting from a single defective gene. Last month, the European Union approved Glybera for treatment of a rare genetic disease, making it the first gene-therapy medicine approved in the Western world. The approval comes amid a flurry of research showing broader promise for the approach in a range of disorders, from a rare form of blindness to hemophilia to heart failure. Though outright cures are still elusive, gene therapy "is beginning to emerge as a meaningful clinical" strategy, says Stephen J. Russell, director of molecular medicine at the Mayo Clinic in Rochester, Minn.