The age of gene therapy--the treatment of disease by genetic engineering--began on September 14, 1990, when a four-year-old girl suffering from a hereditary immune deficiency was transfused with her own white blood cells that had been mixed with the gene needed to cure her. The doctor in charge of the treatment, W. French Anderson, had labored long and hard not only in the laboratory to make this therapy a reality but in the halls of government as well, working his clinical approach or protocol through a myriad of bureaucratic and scientific review boards. Gene therapy, like all revolutionary procedures, had as many detractors as supporters: the specter of genetic designing hovers over the field. But Anderson had insisted to the committees that he was concerned with curing the sick, not creating test-tube super humans. The test--the first ever approved gene therapy--was allowed to proceed as scheduled. It was the pinnacle...