Plasmid-based vectors, advantages

List the advantages of plasmid-based gene medicines over viral vectors. 

The system used to deliver the desired gene into the cells, called the gene therapy vector, may be a virus, a plasmid, or even just the naked DNA. The choice of vector is based on the difficulty of getting the gene into the cell, the amount of DNA the vector can carry, the size of the gene sequence needed to provide the correct protein, and the effects the vector may have on the body. Each type of vector has advantages and disadvantages. 

The rAAV vectors have theoretical advantages as vehicles for human gene therapy, because they are based on a virus that is nonpathogenic and has a natural mechanism for long-term persistence in human cells (16-18). rAAV vectors were prepared by generating proviral rAAV vector plasmids deleted for the viral pro-... 

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