Biology

Gene therapy was originally developed as a cure for diseases that are inherited, for example, cystic fibrosis.  This medical procedure involves the introduction of particular normal genes into cells containing dysfunctional, non-functional or mutant copies of those genes so as to restore normalcy.  But, studies on cancer have revealed that even though many of the diseases that involve multiple gene defects are inherited, nearly all types of cancers can be described as acquired genetic diseases.  These kinds of diseases result from changes in structure in either the activity of genes or in cellular genes.  Further research is required before gene therapy can be effectively applied to such diseases.
   
There are two main types of gene therapy (1) Somatic gene therapy, applied to adult cells and (2) Germline gene therapy, targeting sperm cells as well as eggs.  As somatic cells do not produce offspring, somatic gene therapy involves treatment of these cells with the insertion of an agent that contains a vector or modified gene into the human body.  In ex vivo somatic gene therapy, cells are modified outside of the human body before being transplanted into the body.  In vivo somatic gene therapy, on the other hand, modifies cells within the human body without bringing them out.
   
Somatic gene therapy has no effect on the offspring of the individual undergoing treatment (Types of Gene Therapy Explained).  On the contrary, germline gene therapy is used during the reproductive process to manipulate stem cells, oval or sperm cells in order for the change to be transmitted to the descendant(s) of the persons being treated.  As questions on ethics surround this type of gene therapy  despite the fact that it promises to help people who are suffering from genetic disadvantages to become capable of living and reproducing like others  it has been mostly used on animals thus far.
   
There are three techniques of gene therapy gene insertion, gene modification and gene surgery.  Although gene insertion is not a popular technique of gene therapy, it is worth understanding given that this technique sheds light on risks involved in gene therapy.  The following passage explains all three techniques
       
Gene insertion involves simply adding the normal version of a defective gene to the
genome of the affected cells.  When this gene is expressed, it could produce sufficient
quantities of a missing or defective protein or enzyme, thus curing the disease.  This
method could potentially be dangerous, however, because a randomly added genetic
sequence could disrupt the function of another vital sequence.  For this reason, the other
two methods are being looked into as ideal future methods of gene therapy.
             
The second approach, gene modification, entails the direct chemical modification of the
abnormal DNA sequence in an effort to duplicate the normal sequence in an abnormal cell.
       
This strategy is much less likely to disrupt the function of other genes because no new
sequences are introduced.
             
The third approach, called gene surgery, is considered to be the ultimate goal of gene
therapy.  It involves the removal of the precise genetic sequence that is defective, and
replacing it with a cloned copy of the normally functioning sequence.  This strategy is the
least likely to cause unwanted side effects, but it is also the most advanced and therefore is
not possible in the near future.

As an example, gene surgery may be used in the treatment of the sickle-cell condition.  Sickled-celled anemia may result when abnormal hemoglobin proteins are produced in the human body. This abnormal production is caused by a defect in the amino acid sequence of the vital hemoglobin molecule (Curran  Koszarycz, 2004). In a dysfunctional hemoglobin protein, the amino acid valine would substitute itself for amino acid glutamic acid (Curran  Koszarycz). This unsuitable valine would be a result of an error in the nucleotide codon, which is in the DNA molecule (Curran  Koszarycz).  Thus, GUANINE-THYMINE-GUANINE (GTG) replaces GUANINE-THYMINE-CYTOCINE (GTC)  an apparently insigificant transcription error.  Even so, this error may lead to synthesis of the abnormal hemoglobin molecule.
   
The good news is, of course, that gene surgery may correct this mistake by removing the inappropriate GTC sequence and replacing it by the appropriate GTC codon (Curran  Koszarycz). This would permit the synthesis of the normal hemoglobin molecule (Curran  Koszarycz). What is more, although the procedure is still in its experimental stages, it has the capacity to alleviate human suffering caused by a variety of genetic problems. Indeed, this procedure could be extended to several genetic conditions (Curran and Koszarycz).
   
Apart from the potential benefits of gene therapy already described, this medical treatment can be used to treat Huntingtons disease.  Moreover, gene therapy has been successfully used in the production of medicines (Anissimov, 2010).  Other successes of gene therapy include treatment of severe combined immunodeficiency, thalassaemia, inherited retinal disease and some types of cancers, in addition to reprogramming of T-cells to attack cancer cells (Anissimov).  Unusual immune disorders may also be treated by gene therapy (Stafford  Mannor).  As an example, two girls suffering from ADA (adenosine deaminase) deficiency have been successfully treated with gene therapy.  
   
As gene therapy is still a new form of medical treatment, there have been failures observed as well.  Jesse Gelsinger died due to side effects of gene therapy only four days after receiving the treatment.  Gene therapy also caused leukemia in two children being treated for a rare immune disorder.  Besides the risks of gene therapy already described, this treatment may lead to undesirable changes in reproductive cells.  Additionally, as gene therapy typically engages viruses for the delivery of genes to cells, it is possible that viruses would spread beyond the targeted cells or result in disease.  It is further possible for the immune system to attack viruses introduced through gene therapy, thereby resulting in toxicity, organ failure or inflammation.

Opinion
Regardless of whether the actual costs of gene therapy outweigh its actual benefits at present, the fact remains that this medical treatment has been made famous through intense political debates involving questions of ethics.  In fact, the stance that a political leader takes toward stem cell research  to eventually improve germline gene therapy  can affect his or her political career.  This is like the abortion debate, with the difference that stem cell research promises to enhance public health.  After all, with gene therapy it is possible to control problems related to genetic defects in entire populations.
Then again, nobody can be forced to undergo medical treatment to stop the transmission of genetic defects.  There are universal ethical guidelines applied to all areas of medicine, including gene therapy. These guidelines concern autonomy, justice, beneficence, and nonmaleficence. Autonomy refers to the ability of individuals to govern themselves as well as to make reasoned decisions with regards to the medical treatment they must undergo. The ethical principle of justice demands that all persons undergoing medical treatment must be treated fairly as well as equally and be given what they rightfully deserve. The last two ethical principles  beneficence and nonmaleficence  are especially important in the area of genetics. After all, genetic defects are a very personal problem for those that suffer from them. Hence, doctors are required to show kindness to those that are suffering from these defects. Furthermore, doctors should seek to protect their patients with confidentiality. Disclosure of the fact that a person is suffering from genetic defects may become a cause of embarrassment for the patient. Thus, genetic therapists are required to avoid harm to their patients through strict confidentiality.
   
A major reason why countless people are against the idea of genetic therapy is that they do not trust their genes in the hands of doctors who are using experimental medical procedures to change lives. Another reason why people oppose the idea of gene therapy is that they have faith that God meant for them to be as they are. The religion with the greatest number of followers is Christianity. And, Christians are meant to be focused on the afterlife at the expense of the present life. Therefore, it makes little difference to them whether their lives are drastically improved in this world or not. They would rather accept the decree of God and live as they are. This belief system has a major effect on peoples autonomous decisions concerning whether or not to use genetic therapy to improve their lives.
Still, advances in the science of genetics are a blessing for those who believe that the benefits of gene therapy outweigh its costs. Such people feel free to improve the quality of their lives through gene therapy, regardless of religious arguments.  Hence, the decision to use gene therapy is made like decisions on abortion, that is, gene therapy is a personal choice.