The insertion of genes (e.g., via retroviral vectors) into selected cells in the body in order to:
- cause those cells to produce specific therapeutic agents (e.g., growth hormone in livestock, factor VIII in hemophiliacs, insulin in diabetics, etc.). A potential way of curing some genetic diseases, in that the inserted gene will produce the protein and/or enzyme that is missing in the body due to a defective gene (thus causing the genetic disease). Approximately 3,000 genetic diseases are known to man. Examples of genetic diseases include cystic fibrosis, sickle cell anemia, Huntington’s disease, phenylketonuria (PKU), Tay-Sach’s disease, ADA deficiency (adenosine deaminase enzyme deficiency) and thalassemia.
- cause those cells to become (more) susceptible to a conventional therapeutic agent that previously was ineffective against that particular condition/disease (e.g., insertion of Hs-tk gene into brain tumor cells to make those tumor cells susceptible to the Syntex drug Ganciclovir)
- cause those cells to become less susceptible to a conventional therapeutic agent (e.g., insert genes into healthy tissue in order to enable that healthy tissue to resist the harmful effects of such conventional chemotherapy agents as vincristine)
- counter the effects of abnormal (damaged) tumor suppressor genes via insertion of normal tumor suppressor genes
- cause expression of ribozymes that cleave oncogenes (cancer-causing genes)
- be used for other therapeutic uses of genes in cells.