Gene therapy is an experiment or a technique where the genes are used for prevention or treatment of a disease. Gene therapy was developed in 1972. Even though the technique is not yet fully developed, it has shown success in some cases. Majority of the gene therapies include the introduction of a normal gene into the genome of an individual for replacement of mutated or abnormal gene that was causing the disease.
TYPES OF GENE THERAPIES
There are two types of gene therapy-
- Somatic gene therapy- in this, the gene transfer takes place in any cell of the human body except the sex cells (that produce sperm or egg). The children of the patients do not get affected by gene therapy.
- Germline gene therapy- in his, the gene transfer takes place in cells producing sperm or eggs. The children and future generation of the patient get affected by this. This is prohibited in various countries.
Presently, the gene therapy on the humans targets the somatic cells. Muscular dystrophy, cystic fibrosis and some genetic diseases can be cured by using gene therapy.
HOW DOES IT WORK?
Gene therapy is used in the cases when mutated genes or abnormal genes become dysfunctional and cannot make a protein. Genetic material is introduced into the body through gene therapy to replace it. By using gene therapy, a normal copy of the faulty gene is introduced which makes the protein function.
A carrier, also known as a vector, is used for delivery of the therapeutic gene to the target cells in the patient. Most commonly used vectors are genetically altered viruses carrying human DNA. The target cells are then infected with the vector for the unloading of genetic material. This helps in transferring the therapeutic human gene to the site which restores the target cell back to its healthy state.
IN A NUTSHELL
Despite the success of gene therapies in treating a number of diseases like some viral infections, inherited disorders, some cancers etc, gene therapy poses some risks. Further research and investigation are required in order to make it risk-free, effective and safe. At present, gene therapy is only used in the treatment of diseases having no other known cures.
In gene therapy, researchers take several approaches including the replacement of mutated gene causing the disease with a healthy gene, or making the imperfect mutated gene to be inactive, or even by introducing another new gene inside the body which is capable of fighting diseases.