Katie Beck
Goshen College
November 15, 2004
Thesis: Faced with different applications for the recent knowledge gained in gene therapy, ethical considerations must be analyzed so that society can move forward with caution.
With the human genome project now completed, identifying our DNA, the next step forward is being taken to analyze this information and apply it in a helpful context. As we discover which genes affect and trigger the different traits humans possess, new questions result pertaining to potential problems in our DNA as well as genetic enhancement opportunities. In theory, once a problem is pinpointed within a person’s DNA, there exists a possibility for correcting this defect. Gene therapy is a technique used for correcting defective genes responsible for disease development. This relatively new idea sparks much controversy when societal implications are examined. Bill Joy, chief scientist and co-founder of Sun Microsystems, comments that “we can easily imagine an arms race developing over GNR [genetics, nanotechnology, and robotics] technologies, as it did with the NBC [nuclear, chemical, and biological] technologies in the 20th century….This time…we aren't in a war …we are driven, instead, by our habits, our desires, our economic system, and our competitive need to know (Joy, 2000)."
This paper provides an in depth look at gene therapy including a description as well as an examination of gene therapy as it affects societal issues. Faced with different applications for the recent knowledge gained in gene therapy, ethical considerations must be analyzed so that society can move forward with caution.
Gene therapy, with its first clinical trial in 1990, is a relatively new field that leaves much open to be explored. The idea of gene therapy focuses on locating the defective gene and treating it so that the fixed gene functions correctly by producing proteins that carryout necessary activity in cell pathways. When treating genes, gene therapy can be categorized as targeting somatic cells or germ-line cells. The former concentrates on treating the individual, while the latter aims to eliminate “bad” genes from the individual as well as their offspring.
Somatic gene therapy up to this point has been used to treat rare, deadly, genetic diseases by the insertion of specific genes into human cells other than the cells directly used in reproduction. One problem is the method of insertion. The methods that transfer the new DNA to a defective cell are referred to as vectors. The most commonly used vectors are viruses, more specifically, adenoviruses or retroviruses ( Adams , 2004). Because of the viruses’ natural ability to get by the body’s immune system and introduce DNA into cells without being detected right away, researchers find them to be a particularly useful tool. First the virus must be stripped of its harmful properties and then forced to take up the corrective DNA. The remaining goal is successful delivery to many cells in order for replication as well as insertion into the correct place in the chromosome.
Delivery can be categorized as ex vivo or in vivo. Ex vivo, the first delivery method used, removes cells from the body in order to modify and correct the DNA. Through the aid of a vector and after cell modification, the cells are transplanted back into the patient where they will replicate. Blood or liver cells are good candidates for this method (“Gene Therapy”, 2004). In vivo delivery, on the other hand, refers to a challenging method of completing the corrective DNA insertion to cells still inside the body. Viruses, as described before are the hopeful means to this method. The process involves inserting a small dosage of treated viruses to first check for an immune response, and then increasing the treatment until enough cells are affected so that there is adequate gene expression.
Although viruses are the main vectors used in gene therapy, there are other vectors of gene delivery that are being explored. Direct introduction of the corrective DNA into a specific tissue, liposomes, and chemically linking the DNA to a molecule that will bind to special cell receptors are all options being tested (“Gene Therapy”, 2004). Perhaps the most hopeful vector is the insertion of an actual genetically engineered full-functioning 47 th artificial human chromosome. Insertion problems that may be prevalent through the other means would hopefully be avoided by this chromosomal addition (“Gene Therapy”, 2004). Because of its biological construction, negative immune responses would hopefully be bypassed as well. The process for gene therapy is complicated by method of delivery, vectors, targeting the right cells, and even inserting the corrective DNA into a workable spot in a chromosome.
One setback for gene therapy was the unexpected death of Jesse Gelsinger in 1999. Death resulted from an immunological response to the viral vector (adenovirus) used in the therapy (Thompson, 2003). This particular case was very controversial because he was a relatively healthy individual who could have survived without treatment. Complications arise from lack of knowledge, differences in the recipient’s bodily responses, and the intercellular pathway relationships resulting from gene expression.
Because of the complexity resulting from multigene defects, somatic gene therapy has been focusing on single-gene defects. It can be approximated that each person carries six defective genes; also, one in ten people have or will develop an inherited genetic disorder. The prevalence of disease caused by single-gene defects motivates a need for continued gene therapy research. There are 2,800 specific conditions known to be caused by mutations in just one of the patient’s genes (Thompson, 2003). Cystic fibrosis, Hemophilia, muscular dystrophy and sickle cell anemia are all examples of single-gene defects that gene therapy has been experimenting with and treating. Exciting applications concerning gene therapy to the top causes of death in society are polygenic defects, such as cancer, vascular disease, and arthritis. (Dimichele, 2003)
Somatic gene therapy treats the individual, whereas germ-line gene therapy goes a step beyond to the potential treatment of future generations. This difference results from the cells that are targeted in the therapy. When stem cells, sperm, or eggs are changed, the result will include effects to future offspring.
Up to this point, there hasn’t been much research done involving germ-line gene therapy. Significant progress would have to be made with somatic gene therapy before it could be expanded to effect future generations. One germ-line modification made in a rhesus monkey involved the insertion of a foreign jellyfish gene. This gene was incorporated into the germ-line and was passed on to the next generation (Wright, 2003). The idea of shifting genetic material from one species to another is very radical (Wright, 2003). Germ-line gene therapy remains at a standstill because of ethical controversy as well as its experimental nature.
Expanding gene therapy to include any changes in a recipient’s genetic make-up (other than for the sole purpose of treating a disease) is referred to as genetic enhancement. Genetic enhancement offers the power to enhance normal functions, much like a type of molecular cosmetic surgery. This idea could potentially be carried out through somatic gene therapy or even germ-line gene therapy. Putting limitations on genetic enhancement and not on somatic gene therapy leads to debates concerning definitions of what a disease is versus what can be defined as normal. Disease that results in death is easy to define; however, the line becomes blurred when discussing disability.
Growth hormones are one example of a treatment that has now become questionable as to who classifies as a valid recipient (Dimichele, 2003). Human Growth Hormone (HGH) is a treatment that was first administered to children who lacked the ability to produce the normal growth hormone. As one would expect, this technology led to the following question: what is normal height? The market soon expanded to give children in the lowest 10% regarding height the opportunity to purchase this treatment, thus enhancing their physical appearance.
The potential problems resulting from genetic enhancement are widespread. At an extreme level, there has been mention of designer humans. Genetically engineering or enhancing specific traits could become a competition. Instead of working on qualities such as muscle mass by the traditional way of lifting weights, you could purchase treatment that would supply you with a “better gene”.
Examining the different facets of gene therapy including somatic gene therapy, germ-line gene therapy, and genetic enhancement allows for knowledgeable discussion of ethical considerations. Ethics are standards of conduct that guide decisions and actions, based on duties derived from core values. For some, this may stem from religious belief, consideration for others, or even thought of potential future effects.
Most people consider somatic gene therapy, applied to treatment of a deadly disease, to be ethical. Research and clinical trials have been cautiously carried out, and most have not been objected to due to the last resort nature of these trials. “ Many advisory bodies (scientific and religious) have noted that somatic gene therapy for disease is ethical and, given the clinical safeguards of informed consent, no different than administration of various drugs or transplantation of various organs to cure or ameliorate debilitating diseases.” (Silva, 2002) It is important to note that disease treatment in these cases refers to diseases that one could not live with. Public confidence can quickly be lost with the publication of one unfortunate clinical trial such as the one noted previously. An aura of fear surrounds experimental research, especially when it isn’t fully understood. Fear fuels negative thoughts that can sometimes be taken to the extreme. However, it may also provide a necessary boundary until more information is known.
Germ-line gene therapy, however, has been experimented with very little. The idea of permanently changing DNA through experimental means holds a lot of power. The decisions made today would have a certain direct effect on tomorrow. Some believe gene therapy should be prohibited arguably due to “playing god” (Williams, 2002). Others are not opposed to germ-line therapy, as long as it is proven safe and successfully corrects some unlivable genetic disease. “It is entirely in keeping with our calling to care for the earth and our fellow humans to improve that which has been entrusted to us.” (Wright, 2003)
Genetic enhancement raises the most eyebrows because of its non-restrictive manner. It would seem that any trait possessed would be better if enhanced. It can be debated that the definition of therapy would inevitably expand to encompass more and more enhancements. Enhancement would spread because perceived risks would diminish as more cases turned out successful. The enhanced trait would eventually come to be seen as the normal condition and the cycle would continue. Enhancements would be one other way for a person in society to hold more power.
“The question of what constitutes the normatively human is the most important issue that lurks in all the more specific and concrete problems we face when ethical issues are raised about developments in the field of genetics (FitzGerald, 2002).” This quote perhaps gets to the core of the debate amongst gene therapy treatments. Is it right to classify one gene, thus one trait, as better than another? Is it ethical to say that for example a hearing disability is not normal therefore must be “fixed” by gene therapy? The definition of normal is not static; in fact, normal is seen differently depending on time period and even presently through different cultures.
Pressure to conform to the normal condition would result in less biodiversity. Less variance in our genome would result in a decreased ability for survival. Some genes that may be considered disease, such as sickle cell anemia, are actually seen as benefits in some contexts. In areas where malaria is prevalent, persons with this genetic defect are better equipped for survival. Diversity gives a species more flexibility for survival when faced with environmental changes.
Potential future effects abound when assessing the social, legal, and health areas connected with gene therapy. Gene therapy could increase the social gap between people with medical access and the means to get it and those without. Would definitions of disability and disease be forced upon the legal system or left up to an individual’s interpretation?
Somatic gene therapy poses the risk of creating a higher need for medical attention in future generations. The treated individual would live to reproduce, thus creating a line of dependency. Is it then more ethical to allow for germ-line gene therapy? This would solve the health problem for future generations, but would in turn provoke other questions. Do humans have the unborn right to a natural genome (untreated)? There are also concerns and risks that we are unaware of. At this point I think that somatic gene therapy should be used on a small basis, not germ-line gene therapy, due to their experimental nature. I also think it is unethical to enhance a trait by gene therapy in order for a more positive self image or power issues. Genetic enhancement poses the risk of creating yet another opportunity for power imbalances in society.
When faced with the knowledge we have gained and will continue to learn about our genome, there is a certain inevitability of technology such as gene therapy. Inevitability encourages passivity and acquiescence. “It discourages meaningful public involvement and inhibits scientists from considering the social implications of their research choices (Dimichele, 2003).” Because we have the technology or ability doesn’t infer that it is right and just to use the treatment. I believe the future use of gene therapy should proceed with caution and with an attitude of awareness.
I feel that as a part of society there is a certain responsibility that each person has toward themselves as well as humankind. Each must rise to the challenge of educating themselves in order to be an active part of the living world. It is our duty to think about our actions and their potential effects in order to make informed decisions. Because of our ability to reason, we are held accountable.
As a Christian biologist, I see an undeniable advantage of gene therapy and the potential for genetic debilitating disease treatment. I also feel hesitation on making any radical movements toward much use of gene therapy at this point. Genetic enhancement is an unhealthy way to go about self improvement. It opens the door for an increase in prejudices and barriers amongst people. Even though in the future we may have the technology for genetic enhancement, social effects far outweigh any benefit an individual would derive from the treatment. The notion of normal should not be a motivation for change. Work should be done to foster a culture that embraces diversity. Challenges unite individuals as well as conflict can bring about positive change.
As we sit amidst the genetic revolution there will be many questions that challenge our ethics. The gain of knowledge doesn’t make society wise, but generally poses more controversies and tough decisions to make. Finances, politics, and religion are all tied up in the decisions we face every day. The future cannot be ignored; gene therapy should continue to be researched with the emphasis on debilitating disease treatment.
Adams, Harry. (Spring 2004). A Human Germline Modification Scale. Journal of Law, Medicine & Ethics, 32 , (1), pp164-174.
Dimichele, D., Miller, F. G., & Fins, J. J. (March 2003). Gene Therapy Ethics and Haemophilia: an Inevitable Therapeutic Future? Haemophilia, 9, (2), pp 145-53.
FitzGerald, Kevin T. (August 2002). Knowledge Without Wisdom: Human Genetic Engineering without Religious Insight. Christian Bioethics, 8, (2), pp147-63.
“Gene Therapy”. (October 2004). Human Genome Project Information. http://www.ornl.gov/sci/techresources/Human_Genome/medicine/genetherapy.shtml#status.
Joy, Bill. (April 2000). Why the Future Doesn’t Need Us. Wired, 8, (4).
Silva, Fred G. (September 2002). Ethics of the New Biology and Genetic Medicine (Molecular Ethics). Pathology International, 52, (9), pp555-62.
Thompson, Richard E. (May 2003). Does Patenting Genes Change the Meaning of Life? Physician Executive, 29, (3), pp40-43.
Williams, D. (December 2002). Public Confidence in Medical Technology. Medical Device Technology, 13, (10), pp11-3.
Wright, Richard T. (2003). Biology through the Eyes of Faith. New York : HarperCollins Publishers, Inc.