유전자치료 : 기술적 난점, 규제 현황, 윤리적 쟁점*

Gene therapy, a novel approach to treat, cure, or ultimately prevent disease by changing the expression of a person's genes, is still in its infancy. Current gene therapy is primarily experimental, with most human clinical trials only in the research stages. There are three major hurdles that prevent researchers from developing successful gene therapy techniques. The first hurdle is the safety of the gene delivery tool. Viruses, the most common vectors, while effective in delivering therapeutic genes into human cells, introduce other problems to the body--toxicity, immune and inflammatory responses. The Second hurdle is understanding gene function. Of the estimated 35,000 human genes, scientists know the function of less than one third of them. The third hurdle is multigene disorders. With very few exceptions of genetic diseases, most disease involve the interaction of several genes and the environment.

With a set of extremely strict regulations, the NIH in the U.S. took the lead in regulating gene therapy from mid 1970s to early 1990s when it classified gene therapy to be an experimental human research. Since the FDA's takeover in late 1990s, however, gene therapy has usually been considered as a pharmaceutical product. Similarly, the Korean FDA is now in charge of regulating gene therapy in Korea. There are two guidelines prepared by KFDA available for gene therapy, both of which was recently drafted.

There are seven major ethical questions concerning gene-therapy research. First, what is the disease to be treated? Second, What alternative interventions are available for the treatment of this disease? Third, what is the anticipated or potential harm of the experimental gene therapy procedure? Four, what is the anticipated or potential benefit of the experimental gene therapy procedure? Five, what procedure will be followed to ensure fairness in the selection of patient-subjects? Six, what steps will be taken to ensure that patients, or their parents or guardians, give informed and voluntary consent to participating in the research? Seven, how will the privacy of patients and the confidentiality of their medical information be protected? After short discussion of each question, this article concludes with the remark that, unlike germline gene therapy, somatic cell gene therapy seems morally acceptable, as long as the due procedures have been taken.