What is gene therapy?
Gene therapy is the process of introducing DNA into cells in an effort to treat or prevent disease. When a gene mutation (a permanent alteration in the DNA sequence) causes a protein to be missing or faulty, gene therapy may be able to restore the function of that protein by replacing the gene, introducing a healthy copy of the gene or by turning off genes that are causing issues.
The new genes are inserted into cells with either a viral or non viral genetically-engineered vector, a "delivery vehicle" carrying the genetic material. Modified viruses with the infectious capability turned off are used as vectors, because of their natural ability to invade the target cell, delivering the new gene. The vector can be introduced in one of two ways — outside or inside the body.