Gene+Therapy

Gene therapy is considered to be the therapy of the 21st century and has become a hot area of research because it aims to eliminate rather then symptoms of diseases. Gene therapy could be used to treat both genetic and non-genetic disorders. Genetic disorders caused by a mutation in a specific gene can be treated by delivering a copy of normal functioning DNA to the target cell or tissue to promote proper replications. [i] For non-genetic disorders DNA can be delivered to the target to stimulate an immune response, whether that be producing genes that induce cell death, production of genes that will modify the cellular information or genes that produce therapeutic proteins with specific functions. [ii] Two different approaches have been developed for gene therapy; //**Ex vivo**// and **//In vivo//** gene therapy **//Exo Vivo -//** In this approach specific cells are isolated and purified from a patient. The cells are then genetically modified and then re-infused to patient. [iii] **//In Vivo-//** This strategy involves direct gene transfer to tissue of patients either by delivery of Naked DNA or DNA in a vector. [iv]
 * Gene Therapy **



The goal of this strategy is to achieved expression of transgenes in target tissue for the require amount of time, in the appropriately regulated form and with no major side effects cause by interactions with the host genome.

The simplest method of gene therapy is injection of naked DNA plasmid, however this methods has major draw backs because of low transfection efficiencies and short term expression. Delivery and transfection efficiencies can be increased by packed DNA in a carrier first, also known as a vector.

[i] Orkin SH: Molecular genetics and potential gene therapy. Clin Immunol Immunopathol, 1986; 40: 151 – 6 [ii] Rubanyi GM: The future of human gene therapy. Mol Aspects Med, 2001; 22: 113 – 42 [iii] Hauser H, Spitzer D, Verhoeyen E et al: New approaches towards // ex vivo //and // in vivo //gene therapy. Cells Tissues Organs, 2000; 167: 75 – 80 [iv] Chan L, Fujimiya M, Kojima H: // In vivo //gene therapy for diabetes mellitus. Trends Mol Med, 2003; 9: 430 – 35