Gene therapy is an experimental technique that involves the therapeutic delivery of the conventional factor into cells within the place of a defective sequence to correct genetic disorder and hereditary diseases during which a defective allelomorph is replaced with a purposeful one. Gene has nice potential to forestall and eliminate hereditary diseases like pancreatic fibrosis and hemophilia and its use as a potential cure for the cardiovascular disease, AIDS, and cancer. The stem is being used as a vehicle for gene therapy. Embryonic (ES) Cells are often sequentially changed to introduce the therapeutic gene.