What is Gene Therapy?

Gene Therapy is an approach to treating diseases or genetic abnormalities at the genetic level. This therapy uses DNA as a medicine to treat disease.

Gene Therapy may involve replacing an abnormal or absent gene with a normal one, removing a malfunctioning gene or introducing a new gene to fight disease or for other reasons. This is considered an experimental therapy which is currently being conducted in clinical trials.

As defined by the American Society of Gene Therapy:

• “It is an approach to treating disease by either modifying the expressions of an individual’s genes or correction of abnormal genes. By administration of DNA rather than a drug, many different diseases are currently being investigated as candidates for gene therapy. These include cystic fibrosis, cardiovascular disease, infectious diseases such as AIDS and cancer.”

While Gene Therapy is the replacement of DNA, Cell Therapy is a different type of therapy whose treatment replaces the entire cell (examples include bone marrow or blood transfusion). It’s obvious that often these two therapies will overlap.

Gene Therapy can be carried out at several levels.

• Somatic Gene Therapy is the most common type of Gene Therapy targeting abnormal or absent genes which will result in treating a single patient and does not change hereditary genetics (genetics for the patient’s offspring).
• Germline Gene Therapy occurs at the primary level of the egg and sperm. There is a potential to add or remove DNA which has an effect on hereditary diseases or simply changing the DNA for future generations. This is considered very controversial therapy.

The Center For Genetics Education provides a fact sheet on the ethics and safety of Gene Therapy.

Obviously, in order for Gene Therapy to be successful scientists must have the full understanding of human DNA.

What is the Human Genome Project?

First what is a genome?

A genome is a complete set of DNA, including all of the associated genes

The Human Genome Project’s task was to map the more than 3 million base DNA pairs.

This massive international initiative was supported by The U.S. Department of Energy, Office of Science and the National Institutes of Health. Information on the Human Genome Project is available at the website of The U.S. Department of Energy, Office of Science.

Gene Therapy in the treatment of cancer includes scientific studies into topics such as:

• replacing altered genes with healthy genes
• adding genes that will improve the immune system and fight cancer
• inserting genes into cancer cells to make them more sensitive to chemotherapy or radiation
• introducing genes that will destroy cancer cells

For more information on Gene Therapy and the treatment of cancer visit the National Cancer Institute site.

Resources and Information for current clinical trials in cancer gene therapy:

The Alliance for Cancer Gene Therapy

The National Cancer Institute

M.D. Anderson Cancer Center

Genetech Bio Oncology

Battling Books:

Gene Therapy For Cancer by Kelly K. Hunt, Stephan A. Vorburger, and Stephen G. Swisher (2007)