Gene therapy is a relatively new type of treatment compared to other modalities such as surgical intervention and drug therapy. Unfortunately, gene therapy is not yet a reality. However, this type of treatment continues to show promise due to the wealth of molecular information about human disease that has been accumulated in the past two decades. This information has a high potential for therapeutic benefit because the molecular basis for many diseases has been identified (1 –3 ). It is clear that the introduction of DNA that codes for therapeutic translation products is a rational strategy for correcting diseased or dysfunctional cells. This type of therapy, gene therapy, is particularly promising for the treatment of cancer and metabolic diseases. It also has a high potential for vaccination against disease.
