Gene Therapy: Ethical Issues

How do researchers determine which disorders or traits warrant gene therapy? Unfortunately, the distinction between gene therapy for disease genes and gene therapy to enhance desired traits, such as height or eye color, is not clear-cut. No one would argue that diseases that cause suffering, disability, and, potentially, death are good candidates for gene therapy. However, there is a fine line between what is considered a "disease" (such as the dwarfism disorder achondroplasia) and what is considered a "trait" in an otherwise healthy individual (such as short stature). Even though gene therapy for the correction of potentially socially unacceptable traits, or the enhancement of desirable ones, may improve the quality of life for an individual, some ethicists fear gene therapy for trait enhancement could negatively impact what society considers "normal" and thus promote increased discrimination toward those with the "undesirable" traits. As the function of many genes continue to be discovered, it may become increasingly difficult to define which gene traits are considered to be diseases versus those that should be classified as physical, mental, or psychological traits.

To date, acceptable gene therapy clinical trials involve somatic cell therapies using genes that cause diseases. However, many ethicists worry that, as the feasibility of germ line gene therapy improves and more genes causing different traits are discovered, there could be a "slippery slope" effect in regard to which genes are used in future gene therapy experiments. Specifically, it is feared that the acceptance of germ line gene therapy could lead to the acceptance of gene therapy for genetic enhancement. Public debate about the issues revolving around germ line gene therapy and gene therapy for trait enhancement must continue as science advances to fully appreciate the appropriateness of these newer therapies and to lead to ethical guidelines for advances in gene therapy research.