Good and Bad of Gene Therapy
Genes refers to the basic physical as well as functional units that play part in the hereditary process. They have specific base sequences that are involved in encoding information on the way proteins are made. The alteration of the gene results in a protein that is not in a position to carry out the desired function in the body resulting in genetic disorders. To solve these genetic disorders, a technique known as gene therapy was developed. The technique, aims at correcting the defects that are in the gene that is responsible for causing the disease to develop (National Institutes of Health, 2012).
/>
There are several approaches that researchers have developed for correcting the genes that are known to be faulty. One of the approaches is the insertion of a normal gene into a non-specific location along the genome in order to replace the gene that is not functioning normally. The other approach is to swap the abnormal gene with a normal gene using homologous recombination process. The other approach is to repair the abnormal gene by use of the selective reverse mutation in order to return the normal function of the gene (National Institutes of Health, 2012).
The insertion of a gene directly does not return the normal function of the gene. Instead, the gene is inserted into the cell carried in a vehicle called a vector. The vector is engineered genetically to enable the delivery of the gene into the cell. Most of the vectors are viruses since they have the capability to deliver the gene to be introduced in the cell by infecting the cell. The viruses are usually modified to make sure that they cannot lead to disease after they are introduced in the cells. Different viruses deliver the new gene differently. For instance, retroviruses deliver the new gene by integrating their genetic content, which includes the new gene, into the chromosomes that are in the cell. On the other hand, the adenoviruses only introduce their genetic content into the nucleus but they are not able to integrate the genetic content into the chromosome of the cells (Edelstein, 2013).
For the vector to be introduced into the body it is either injected or intravenously introduced into the specific tissue where individual cells take up the vector. In a different way, a sample of cells from the patient may be taken out and the vector introduced in the laboratory. Once the cells have taken in the vector, they are returned into the patient where once successful; the new gene that the vector has delivered produces the functional protein.
There are a number of good things associated with gene therapy. The most essential thing is that many of the diseases that the technique targets, the genetic disorders, have no other way to cure that is available. The only way that the genetic disorders may be cured is by replacing the gene that has failed with one that is normal. This makes gene therapy to be the only hope for getting treatment for these disorders.
The processes of gene therapy may target the cells of the reproductive system, which are known to be carriers of diseases such as cystic fibrosis, cancer or the Parkinson’s disease. The success of this process may enable the affected children or patients to be free of the gene that is defective and sometimes eradicate the disease completely. This gives the patient a chance to enjoy normal life once the process is successful.
Since most of the diseases that are targeted by the gene therapy have no medication, the success of the gene therapy process may ensure that the root cause of disease is removed rather than easing the symptoms of the disease.
Other than curing the existing disease, gene therapy may also be applied to prevent disease that may be coming up progressively. This may be done to by rectifying the mutation in the gene that is associated with the disease early before the medical conditions associated with the disease are expressed. For instance, preventive gene therapy has been studied in a condition called Retinitis Pigmentosa. Incidences of blindness are detected early before there are any signs that have manifested. A number of preventive gene therapies are employed in order to handle one condition (Cepko, 2012).
However, gene therapy has a number of challenges. There is a lot that is not known concerning the treatment, which means issues with the safety of the process are not well understood. The current knowledge and understanding concerning gene therapy is heavily based of scientific theories rather than on concrete evidence. This is a disappointment when gene therapy is compared to drug therapy that has been tested and determined to be safe. These issues may however be improved through advancements in research.
A number of clinical trials that have been carried out have only had effects that have lived only for a short time. The inserted gene should remain retain its function and the cells that has the gene should be stable and live for a long time for the effect to be realized. There are however issues with the way the vector is integrated into the cells where some processes are not successful. In other cases, the cells that receive the therapeutic gene may be undergoing rapid division and this prevents the therapeutic process from achieving a lasting benefit. This causes the patients to go through a number the same gene therapy in order to increase the efficacy (ORNL, 2011).
The vector introduced into the body may be attacked by the immune system as a foreign object. The risk of the vector being attacked by the immune system has reduced the effectiveness of the gene therapy process. The immune system is also capable of invading the molecules that have been seen before and this offer difficulty while repeating gene therapy in patients (ORNL, 2011).
Viruses, which are mainly used as the vectors for carrying the therapeutic gen in gene therapy, have been reported to present a number of challenges to the patients. These challenges include immune response, toxicity, as well as, inflammatory responses. There is also the issue of gene control where the gene introduced may have no control over its expression. The vector may also fail to get to the cells that it was initially targeted to invade. Additionally, there are fears that the virus may regain its virulence capability once inside the patient and thus lead to disease (ORNL, 2011).
Other than the scientific disadvantages associated with gene therapy, there are other ethical issues that has come up following the new developments. Gene therapy is very intrusive in nature and may lead to patients being aware of information involving their genetic make-up that they were never supposed to know. This information includes risk of some diseases and therefore negatively affects the lives of the patient (ORNL, 2011).
Gene therapy is a course that is worth exploring although the good things with the processes are outweighed by the bad things associated with gene therapy. The fact that disorders that exist from birth have a chance of being rectified and have a normal life is a great milestone in dealing with these disorders. Researchers are faced with the task of overcoming the challenges that face gene therapy process before the process can be practical. Better ways of delivering the gene to the target cells should be developed and ensure that the control mechanisms for the new gene are precisely laid down.
The challenges associated with gene therapy can be overcome through research. Gene therapy offers an exciting different approach in the way diseases can be cured. In the future, gene therapy is expected to be applied on most of genetic conditions changing the medical field significantly. Scientists are continually discovering more genes together with their functions. This understanding will enhance the potential behind gene therapy technology where a combination of effective therapeutic genes and proper vectors for delivering the gene that will express in the cell under controlled environment is critical (Leiden, 2000).
Reference List
Cepko, C. L. (2012). Emerging Gene Therapies for Retinal Degenerations. Journal of Neuroscience, 32(19), 6415–6420.
Edelstein, M. (2013). Gene Therapy Clinical Trials Worldwide. Retrieved March 14, 2013, from http://www.wiley.com/legacy/wileychi/genmed/clinical/
Leiden, J. M. (2000). Human Gene Therapy. Circulation Research, 86, 923-925.
National Institutes of Health. (2012). Gene Therapy. Retrieved March 14, 2013, from http://ghr.nlm.nih.gov/handbook/therapy?show=all
ORNL. (2011). Gene Therapy. Retrieved March 14, 2013, from Oak Ridge National Laboratory: http://www.ornl.gov/sci/techresources/Human_Genome/medicine/genetherapy.shtml
