Gene therapy: panacea or placebo? II. Main applications of gene therapy

For most disorders the ideal goal of gene therapy is the repair of the mutated gene in the target tissue. However, the techniques required for such an approach are still at an early stage of development. Most current research is directed towards delivery of normal gene sequences in order to generate active protein and compensate for the lack of endogenous production. This approach may be suitable for the treatment of recessive monogenic disorders, but is inappropriate for dominantly inherited disorders. Therefore, gene therapy was originally intended as a most promising approach for the treatment of inborn errors of metabolism. However, apart from the correction of heritable genetic disorders, gene delivery has many potential applications including treatment of malignancies, atherosclerosis and vascular proliferative disorders, rheumatoid arthritis and viral infections. The authors discuss significant examples marking progress in the development of gene therapy for specific diseases, present some hopes and hurdles that have arisen from some recent preclinical and early clinical trials.