Limitations of informed consent for in utero gene transfer research: implications for investigators and institutional review boards.

Only 10 years after the first human gene transfer protocols were approved for adults and children, researchers have begun to consider gene transfer on the fetus. While preliminary animal research is ongoing, the enthusiasm and pace of research in this area suggest that human protocols for in utero gene transfer research may be seriously considered in the foreseeable future. Federal guidelines for fetal research rely on minimizing risk and informed consent to protect the "rights and welfare" of both the fetus and pregnant woman. However, in utero gene transfer research poses special challenges to informed consent. This research represents an innovative approach for very ill subjects and takes place in the prenatal setting. These features may converge to undermine the expectant parents' comprehension of, and voluntariness for participation in, research. In this case, informed consent may not be able to bear the weight of adequately protecting the fetus from undue research risks. To compensate for this limitation, and using the regulations for pediatric research as a guide, a greater emphasis should be placed on the benefit/harm assessment rather than informed consent. Selecting diseases/patients where good alternative treatments exist may maximize informed consent, yet this may be a trade-off that exposes the fetus to greater relative risks. On the other hand, selecting diseases/patients without good alternative treatments to prolong life may convey an overestimation of the potential benefits of these interventions, and although care should be taken to strive to improve understanding of these limitations, misunderstanding may persist. However, selecting diseases/patients with no good alternatives might make serious risks more tolerable, and this should take precedence over informed consent. The limitations of informed consent brought into focus by the special features of in utero gene transfer research may be relevant to a broader range of innovative investigations.