Are there different types of gene therapy?
Yes. Gene replacement therapy involves identifying a faulty gene, applying a piece of DNA in its correct form though a viral vector (or carrier molecule) to the gene in an effort to override the faulty gene with the correct copy. While current delivery models and strategies are continuously being investigated, the most common approach is through viral vectors (carrier molecules containing the virus). As viruses can attach themselves to healthy cells, viral vectors are genetically modified to represent normal DNA allowing for re-injection to compromised cells in an effort to restore the faulty gene to a healthy/ normal state.
Other types of gene therapies include delivery of RNA or DNA sequences used either to suppress or “knock out” unwanted gene function, correct a defective gene through DNA repair within cells or to suppress an oncogene (gene that in certain circumstances can transform a cell into a tumor cell).
Vectors and cells can also be used to promote an immune response to tumor cells and pathogens by expressing theses antigens in immune responsive cells in combination with factors which enhance the immune response.