Molecular Genetics - Gene Therapy

Gene Therapy

A mutation in a gene can result in a severe medical condition. A protein encoded by a mutated gene may malfunction and cells that rely on the protein might therefore fail to function properly. This can cause problems for specific tissues or organs, or for the entire body. This might manifest through the course of development (like a cleft palate) or as an abnormal response to stimuli (like a peanut allergy). Conditions related to gene mutations are called genetic disorders. One way to fix such a physiological problem is gene therapy. By adding a corrected copy of the gene, a functional form of the protein can be produced, and affected cells, tissues, and organs may work properly. As opposed to drug-based approaches, gene therapy repairs the underlying genetic defect.

One form of gene therapy is the process of treating or alleviating diseases by genetically modifying the cells of the affected person with a new gene that's functioning properly. When a human disease gene has been recognized molecular genetics tools can be used to explore the process of the gene in both its normal and mutant states. From there, geneticists engineer a new gene that is working correctly. Then the new gene is transferred either in vivo or ex vivo and the body begins to make proteins according to the instructions in that gene. Gene therapy has to be repeated several times for the infected patient to continually be relieved, however, as repeated cell division and cell death slowly randomizes the body's ratio of functional-to-mutant genes.

Currently, gene therapy is still being experimented with and products are not approved by the U.S. Food and Drug Administration. There have been several setbacks in the last 15 years that have restricted further developments in gene therapy. As there are unsuccessful attempts, there continue to be a growing number of successful gene therapy transfers which have furthered the research.

Major diseases that can be treated with gene therapy include viral infections, cancers, and inherited disorders, including immune system disorders.