Principles and Promise of Gene Therapy

Gene therapy is a relatively recent, and still highly experimental, approach to treating human disease. While traditional drug therapies involve the administration of chemicals that have been manufactured outside the body, gene therapy takes a very different approach: directing a patient’s own cells to produce and deliver a therapeutic agent. The instructions for this are contained in the therapeutic transgene (the new genetic material introduced into the patient). Gene therapy uses genetic engineering—the introduction or elimination of specific genes by using molecular biology techniques to physically manipulate genetic material—to alter or supplement the function of an abnormal gene by providing a copy of a normal gene, to directly repair such a gene, or to provide a gene that adds new functions or regulates the activity of other genes.