Therapeutic cloning applications and biological mechanisms

Therapeutic Cloning

Recent years have seen intense debate on the ethicality of human cloning and therapeutic cloning. While the former involves reproduction of a new human (clone to the adult from whom the DNA was taken), therapeutic cloning has a very different goal. Having said that, therapeutic cloning, too, has been under the spotlight. This paper's purpose is to focus on therapeutic cloning alone and explore the possible pros and cons of the procedure. But, first, it would be important to define therapeutic cloning in order that the discussion that follows is viewed in the correct contextual framework.

Therapeutic Cloning or Somatic Cell Nuclear Transfer is a procedure, which involves removing the DNA from a cell taken from a human, inserting it into the DNA taken from a woman's ovum and giving the resultant ovum an electrical shock to begin the formation of an embryo. The procedure results in a pre-embryo being formed in a small percentage of cases (Robinson).

The pre-embryo that is formed is then allowed to develop and produce many stem cells, post which the stem cells are removed leading to the death of the pre-embryo. The stem cells are then encouraged to grow into either tissue or an organ that is needed to treat a patient. Theoretically, such stem cells can be, therefore, used to develop replacement organs. It is envisaged that therapeutic cloning, if successful, will lead to perfectly matched organs that could be used to save countless number of lives, while increasing the quality of life for innumerable other physically or physiologically challenged people (Robinson).

The other important context that needs to be tabled is the fact that scientists have yet to achieve: a critical first stage in embryonic stem cell research i.e. The ability to consistently isolate embryonic stem cells and grow them into the desired type of tissue; a second stage will be to determine the correct mode of delivery of the specialized cells to the part of the body that is diseased or injured; and finally a third stage will be that of tissue engineering.

It is only once research is successfully conclusive on all the aforesaid steps can scientists even begin to find out if there any long-term benefits; whether the cells multiply as theorized but do not interact, and replace injured cells (Shannon).

Given the current status of therapeutic cloning, as described above, it must be pointed out that the controversy and debate on the desirability or otherwise of the procedure centers around the ethics of the issue, springing from questions on the moral status of the cloned human embryo and the implied consequences of routinizing and legalizing the production and destruction of the same (Berkowitz).

On one end of the spectrum is the view that the cloned human embryo is deserving of no more respect than any other microscopic particle and to that extent, therapeutic cloning does not involve any moral issue regarding the sanctity of human life. At the other end are pro-life supporters who hold the view that any human embryo, irrespective of origin, should get the same respect and rights as any fully developed human being and therefore, therapeutic cloning should be banned. A third view is that while pre-embryos probably deserve less consideration than human beings at later stages of development, therapeutic cloning is likely to lead to systematic disrespect for developing human life (Berkowitz).

Advocates of therapeutic cloning lay emphasis on the possible promise of an exponential leap that the procedure holds: "Three possible examples of therapeutic cloning might include the use of insulin-secreting cells for diabetes; nerve cells in stroke or Parkinson's disease; or liver cells to repair a damaged organ." (Robinson)

Further, they theorize that the method will have untold advantages over current treatments as there would presumably be no danger of rejection of the transplant because the organ's DNA and that of the patient would be an exact match; there would be no need to put donors through the pain and the risk of a potentially shortened life-span; patients would not have to go through interminably long waiting periods; there would be benefits from a brand new organ as compared to replacement organs that may have reduced functionality due to ageing; and last but not least, the method has the potential to cure hitherto incurable diseases (Robinson).

Building on therapeutic cloning's potential to cure diseases, the scientific and pro-choice lobbies point out that researchers can take a diseased cell from an adult (cancer, cardiovascular, Alzheimer's) and use embryonic cloning to create a stem cell line from it.

Studying a stem cell line of this kind will help study how diseases develop as the stem cells differentiate and find remedies to address or regress that action. A case in point, is that hypothetically the way in which embryonic stem cells, cloned from adult cells of an Alzheimer patient, differentiate into brain cells can be compared with the normal function of brain cells, thereby providing valuable insights into the origins and progress of the disease (Barglow).

Recognizing the possible huge gains for medical and behavioral sciences, some countries such as the U.K. have taken a middle-of-the-road approach from the standpoint that "the respect due to an embryo increases as it develops and that this respect, in the early stages in particular, may properly be weighed against the potential benefits arising from the proposed research. The current restrictions and controls on embryo research reflect this latter view, providing the human embryo with a degree of protection in law but allowing the benefits of the proposed research to be weighed against the respect due to the embryo." (Stem Cell Research: Medical Progress with Responsibility)

Among biomedical researchers in the United States, too, there is a broad consensus that the benefits of research cloning of embryonic stem cells may lead to remedies for severe childhood and adult illnesses that afflict millions of people. In fact, in February 2002, the National Academy of Sciences concluded that therapeutic cloning "offers great promise for treating diseases...closing these avenues of research may have real costs for millions of people...." (Barglow)

As a counter to opponents of therapeutic cloning, proponents point out that the current debate over stem cell research can be compared to the 1970s controversy over recombinant DNA technology, which now produces a broad range of medicines, including cancer and diabetes treatments (Barglow). Arising from such arguments, then, is the question of the commitment to freedom to inquire, to improve our condition, and to master our world (Berkowitz).

Proponents of therapeutic cloning also counter ethical concerns by submitting that early embryos or the blastocyst is merely a microscopic particle, "...fertilization is itself a process requiring at least 24 hours to complete...cloning does not require fertilization at all.... While many argue that the blastocyst at this stage is a person in potentia and, therefore, should be treated as such, a core problem is that potency is not act." (Shannon)

The last is precisely the chief concern of the opponents to therapeutic cloning or the pro-life lobby. These critics express the view that a pre-embryo is a latent form of human life and therefore, any research that involves the premature death of such embryos, irrespective of how they were created, is a violation of the principle that human life must be preserved.

The Church, for one, agrees with the above view. In fact, Pope John Paul II clearly expressed the viewpoint during his address to the 18th International Congress of the Transplantation Society: "...methods that fail to respect the dignity and value of the person must always be avoided...attempts at human cloning with a view to obtaining organs for transplants: these techniques, insofar as they involve the manipulation and destruction of human embryos, are not morally acceptable, even when their proposed goal is good in itself." (Pope John Paul II)

Leading from this, critics also point out that therapeutic cloning is worse than human cloning, which at least aims at bringing a human life into existence, and does not harvest certain parts of a developing human life and then discard it. It is the latter aspect that they emphasize must be raised as a social and moral concern. There is also the fear that such research will create a slippery slope that will inevitably lead to reproductive cloning as well (Berkowitz).

Then there is the substantiation of their ethical standpoint from a legal perspective of fundamental human rights to life and dignity being accorded to an unborn child. This is evidenced by the fact that international law states that a pregnant woman cannot be sentenced to capital punishment. The issue of whether a pre-embryo constitutes human life is addressed by countering the very assertion that 14-day-old embryos are not really embryos.

The question here is that when the fate of these clones is determined by the therapeutic benefit to others, and since the line of protection of human embryos would have been arbitrarily set at 14 days, then there is really no reason why fetuses could not be used for the same sort of therapeutic purposes up to birth (An Ethical Assessment of Obtaining and Using Human Embryonic Stem Cells).

Another counter to therapeutic cloning is the possibility of alternative methods to reaching the same goal, methods such as the use of adult stem cells or even the use of stem cells from umbilical cord blood have no moral stigma attached to them. Secondly, there is promising research work being done in these areas. So why experiment with human embryos and run the risk of these being specifically created for destructive experimentation? (The Age, March 2002)

Besides such obvious negatives, another ethical dilemma raised by the subject of therapeutic cloning is the fact that it violates a basic tenet of nature. Currently, establishing a human embryo naturally, or by any of the standard artificial reproductive technologies, involves the fusion of a sperm with an egg. Thus the new organism formed contains genetic information both from the sperm and egg. Cloning, on the other hand, is asexual reproduction as it is done by reproduction of a cell or an organism, usually, but not always, with the same nuclear genome as another cell or organism. This is what ensures the same genetic make up (Cloning: Sometimes Nice and Sometimes Nasty).

True that such embryos are terminated before 14 days in therapeutic cloning but the fact still remains that such procedures are knowingly violating established tenets of nature and could later lead to all sorts of problems. Isn't this exactly what raises fearful images of eugenics and memories of the atrocities of the late nineteenth and early twentieth century?

The opponents to therapeutic cloning also point out that the procedure implies loss of dignity and value of human life given that the ovum needs to be extracted from women. Not only is there some evidence that shows there is a risk of physical injury to at least one percent of such donors, there is also the probability that such woman donors will be putting their body through what's called a super-ovulation process, which may lead to some psychological problems in a few cases. Then there is the very real possibility that the people most likely to be hurt will be women from weaker socio-economic strata as they would be lured by the promise of payment: "...$3,000 to $5,000 each...making their bodies manufacturing plants...." (Shepard)