Prospects of treating neurological diseases by gene therapy.

Neurological disorders represent a major challenge for therapeutic interventions due to the sensitivity and complexity of the CNS and the requirement of the therapeutic agent(s) to have a long-term effect. Gene therapy applications have opened up new possibilities to specifically deliver not only drugs but also small 'drug factories' by non-viral or viral vectors to the target site of action. A number of studies have demonstrated the feasibility of the gene therapy approach in animal models, and the simultaneous engineering of safer and more reliable vectors has moved the technology one step closer to clinical administration. In particular, viral vectors can provide long-term expression extended over one year. Most promisingly, the discovery of RNA interference has provided a novel method of specific gene silencing, which presents the opportunity to develop new therapies for the treatment of neurological disorders.