What are the benefits of stem cells?
The ability of stem cells to transform into fully functional cells represents a potential therapeutic option to replace or repair damaged tissue, effectively reversing the effects of age, disease and injuries. A direct practical implication can be exemplified by the replacement of damaged heart muscle after a myocardial infarction. Due to their potential usefulness, it is estimated that stem cell research has the potential to help more than a hundred million Americans who suffer from injuries and/or degenerative diseases; that number is several times higher if the world population is considered. On the other hand, stem cells can be used to generate artificial tissues where drugs can be directly tested, instead of using animals or human subjects.
What are the ethical implications of embryonic stem cell research?
Stem cell therapies are not really new, bone marrow stem cell transplants have been performed for decades; however, when the procedure to remove stem cells from human embryos was first described (Ref 1998), a strong controversy arose. In order to introduce stem cells as a generalized option to treat diseases, extensive research still needs to be done to identify their capabilities and limitations. On one hand, embryonic stem cells have the potential to cure a number of diseases; however, their study would require destroying human embryos, given this ethical implication, political measures were taken to regulate research of human embryonic stem cells. Among the most debatable ethical implications of destroying human embryos involved religious and political points of views: 1) do embryos have a soul? 2) Can human embryos considered the same as children? And, if so, 3) do they have rights? 4) Is it possible to justify the destruction of a hundred of human embryos if one looks at the greater good of saving hundreds of thousands of human lives, and perhaps preventing another hundred thousand from developing diseases? 5) Since embryonic stem cells do not lose their potential to transform into any type of cells, each of them retain, theoretically, their ability to form a whole similar individual, forming clones, in this case, what happens with the sole of the embryo, is it divided ?
Furthermore, numerous religious and human rights group have shown concerns about the possibility that stem cell research might induce an indiscriminate collection of human embryos, while political groups debate on how will the knowledge will be used.
Do alternatives exist for embryonic stem cell research?
Given the ethical and political limitations of embryonic stem cell research, novel approaches were looked after; thus inducible pluripotent stem cells were identified in adult humans, and techniques were developed to harvest them from tissue samples of living individuals. This reduced the need for embryos or the look for suitable aborted fetuses to work with. Stem cells can also be obtained from placenta, the umbilical cord and placental blood; in addition, fertilized eggs that failed to naturally implant are also a source of stem cells. Since inducible pluripotent stem cells have the ability to be transformed into whole embryos, thus raising the possibility to clone human beings.
Another alternative to decrease the use of human natural embryos is to generate the embryos synthetically, in this process, the nucleus of an unfertilized ovum is replaced by the nucleus of a human cell of an existing individual, then the ovum is stimulated to grow and convert into an embryo. Since the genetic material that this embryo will contain is exactly the same of the individual from which it was extracted, the resulting embryo will be, for practical terms, its clone.
What are the ethical consequences of stem cell cloning of human beings?
Since the potential cloning of human beings, by means of stem cells, was made public, religious and political organisms in several countries, including the USA, called for an immediate ban on human cloning. Researchers claim that cloning humans can actually produce an infinite amount of “spare” parts to replace human damaged organs and tissues, without risking cellular rejection as occurs with the usual transplantation techniques. This poses additional questions and sparked one of the strongest ethical controversies during the last twenty years: 1) if an embryo is created from an existing human being, could it be considered as a separated individual, as if it were a twin? 2) Cloning embryos for later use as spare parts will also require stopping their development, “freezing” them for later use, would this violate the rights of the cloned individual? 3) Once they are grown up to certain stage, their organs and tissues will have to be collected, either killing or disabling the clone, is that the equivalent to disabling/killing another person? 4) Even when a reasonable justification could be found for the above questions, a wider and more general concern was expressed by religious groups, basically, humans are not supposed to play God, in other words, by acquiring the ability to create, modify, and destroy a living individual, at will, humans are locating themselves in a role that traditionally is reserved for deities, a situation that centuries ago could be punishable by death.
From the oldest recordings of civilizations, to our actual society, humans have traditionally opposed to radical changes whose consequences cannot be clearly seen. There is a natural instinct to protect our own species; however, there is a stronger motivation that drives most aspects of human behavior, the struggle for power. While cloning human beings can certainly benefit certain aspects of the human life, it will also give limitless power to a reduced number of individuals that can use it as a powerful bargaining coin. This could represent a potential danger for those who presently hold power in our world. On the other hand, although from an unbiased point of view it is clear that stem cell research and cloning will certainly provide several benefits to humankind, another concern arises: The nature has a way to deal with individuals of any species that cannot fulfill their natural purposes, they degenerate, cannot reproduce and are taken aside from the natural evolution. When a human being suffers a degenerative disease (e.g. cancer), severe genetic disorders or cannot reproduce, their ultimate demise will prevent their susceptibilities, and disorders to be brought into a new generation. If we bypass this mechanism, are we not messing up with the same natural selection process that led to the creation of human beings in the first place? or are we simply naturally selected to extinct our species by trying to play with natural phenomena that we do not fully comprehend and whose long-time implications cannot recognize?