by Ruth Hubbard and Elijah Wald

About the authors: Ruth Hubbard is professor emerita of biology at Harvard University. She writes frequently about the politics of health care, and her works include books such as The Politics of Women’s Biology. Elijah Wald is a freelance writer and musician. This viewpoint is excerpted from their book Exploding the Gene Myth (Beacon Press, 1997).

Attempts to modify the DNA in our reproductive cells (sperm and eggs) or in the cells of early embryos raise . . . troubling issues. If the DNA of these cells is altered, this will not just affect a specific individual. . . . The altered DNA will be passed to future generations in the germ line, which is why this type of DNA manipulation is conventionally called germ-line gene therapy. Let me make clear how it differs from [other...