Gene+Therapy

= Gene Therapy: = =Is an experimental technique that is used to treat or prevent disease.=

How It Works

 * Replacing a mutated gene with a copy of the disease with a healthy copy of the gene.
 * Inactivating, or "knocking out", a mutated gene that is functioning properly.
 * Introducing a new gene into the body to help fight the disease by a carrier called a //__vector__// that is genetically engineered to deliver the gene.


 * __Ex Vivo Transplant__**
 * In some cases of gene therapy the cells from the patients blood or bone marrow are removed and grown in a laboratory.
 * The cells are exposed to the virus carrying the desired gene.
 * The virus goes into the cells and inserts the desired gene into the cells DNA.
 * The cells that are grown in the laboratory are then returned to the patient by an injection through the vein[[image:whsgenetics3/vectors-gene therapy.gif width="270" height="195" align="right"]].


 * __The Vector__:**
 * The vector can be injected or given the through an IV directly into a specific tissue in the body, where it is taken up by individual cells.
 * A sample of the patients cells can be removed or exposed to the vector in a labaratory setting.
 * The cells containing the vector are returned to the patient.
 * If the treatment is successful the new gene that was delivered by the vector will make a functioning protein.

Diseases That Can Be Candidates For The Use of Gene Therapy:

 * Phenylketonuria (PKU)- Can resuult in mental retardation in not treated early.
 * Lesch-Nyhan syndrome-A disease in which the patients are unable to a manufacture a particular enzyme. Which can lead to an impulse for self-mutilation,including severe biting of the lips and fingers.
 * Cystic Fibrosis

What these diseases all have in comon are that the tissues being treated are somatic. Somatic cells include all of the cells from the body,excluding sperm and egg cells. These are not all of the diseases that can be candidates for gene therapy.

If Your Disease Makes You A Candidate For Gene Therapy Treatment:
While a lot of medical conditions and disorders can be treated through the use of gene therapy but other conditions may not be suitable for the gene therapy approach. To know whether or not a disorder is a good candidate for gene therapy the patient should be able to answer these questions: If you can answer yes to questions 4 and 5, then the disorder is most likely a good candidate for the gene therapy approach. .
 * 1) Does the condition result from mutations in one or more genes?
 * 2) Which genes are involved? (The best candidates for gene therapy are the single gene disorders which are caused by mutations in only one gene)
 * 3) You must know the biology of the disorder. (Knowing all you can about the gene factors of the disorder)
 * 4) Will adding a normal copy of the gene fix the problem in the affected tissue?
 * 5) Can you deliver the gene to cells of the affected tissues?

Further Research To Be Done:
Scientists must find a better way to deliver genes and target them to particular cells. They also must ensure that new genes are specifically controlled by the body.