Seasoned science writer Thompson (The Washington Post, Medical News Network) charts the course of the first successful human experiment in gene therapy, begun in 1990. And what a complex course that has been. The prize went to NIH scientist W. French Anderson (now at USC) and colleagues who devised a treatment for ADA deficiency, a rare hereditary disease that gradually destroys the immune system because of the lack of an enzyme to remove toxic waste products from immune cells. Anderson had dreamed of gene therapy long before it was fashionable -- indeed, he was dismissed as a lightweight. Here, Thompson tells all, alternating biographies of the principal players and patients with an explanation of the science of splicing genes. The result is sometimes mechanical -- as though the chapters were written independently -- but, overall, a warts-and-all picture of ambition and competition emerges that includes the detailed story of the rise and fall of Marty Cline. He was the brilliant UCLA investigator who violated all the rules by going abroad to try gene therapy on two thalassemia patients. When word got out (leaked by Anderson, it seems), Cline was fired, lost his grants, and essentially got out of the business. Today gene therapy has been well and truly launched with improvements in techniques and applications to cancer and hereditary disease. Creditably, Thompson elaborates on the problems and politics while also neatly outlining the genealogies of science: who studied in whose lab forging the networks (and rivalries) that are par for the course in science.