The ethics of human gene therapy

The authors of this absorbing new book describe the science of gene therapy in terms easily accessible to the non-specialist, and focus on the controversial ethical and public policy issues surrounding human interventions in human heredity. After a brief survey of the structure and functions of DNA, genes, and cells, Walters and Palmer discuss three major types of potential genetic intervention: somatic cell gene therapy, germ line gene therapy, and genetic enhancements. They start with the current techniques of gene addition, using non-reproductive (somatic) cells in an effort to cure or treat disease. Next they address the technical problems and moral issues facing attempts to prevent disease through genetically modifying early human embryos or sperm and egg cells. These changes would be passed on to future generations. Chapter 4, in many ways the most original part of this volume, confronts the issue of employing genetic means to improve human abilities and appearance. Depending on the technique, such enhancements could affect not only the individuals receiving the intervention but their offspring as well. Three types of genetic enhancements are considered: physical alterations