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, labored 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. But Anderson had insisted to the committees that he was concerned with curing the sick, not creating test-tube super humans. It was the pinnacle of achievement for a man who had spent his career researching human biochemical genetics, hematology, and the synthesis of hemoglobin and proteins.

William French Anderson...