There is no doubt that the cloning of humans has enormous potential in many fields. It seems to solidify, in reality, the procedures that were only seen in sci-fi movies; from the farfetched possibility of an army of cloned soldiers to the more realistic cloning of entire organs for transplants. However, getting to either point requires a lot of cloning experimentation. The questions bioethicists try to answer relate to the delicate line that separates advances in science and issues that relate to human dignity.
Stem Cells from Somatic Nuclear Cell Transfer (SCNT)
SCNT is a procedure where a somatic cell and a germ cell undergo a seemingly simple procedure. The DNA containing nucleus from a somatic cell (from the patient) is removed. The nucleus is then inserted into a germ cell (from a donor) that has its nucleus removed. After a couple of electric shocks designed to fuse the cells and to start the cell division, a blastocyst is formed.
A Tale of Two Cloning: Therapeutic Cloning and Reproductive Cloning
In therapeutic cloning, the blastocysts are then destroyed and the stem cells harvested for research. The benefits of obtaining stem cells in this procedure allows scientists to create a stem cell line with the DNA of the patient who requires the stem cell related therapy; creating tissues that are an exact genetic match of the patients tissues.
The parallel tale is reproductive cloning. In reproductive cloning the cloned blastocyst is allowed to develop further where it is eventually implanted in a uterus and allowed to develop into a separate organism or human (as would be the case of human cloning.)
Cloned Blastocyst versus Fertilized Blastocyst
The question as to whether therapeutic cloning is human cloning boils down to the difference that can be perceived in the two blastocysts of different origins. The argument is that a cloned blastocyst is genetically different from a fertilized blastocyst and has little potential to develop further. However, Dolly the cloned sheep and research says otherwise. This argument also supported the fact that the same genetic obstacles faced by cloned blastocysts may also create a challenge for creating reliable stem cells. Researchers have refuted both these claims (Brambrink T, Hochedlinger K, Bell G, Jaenisch R. “ES cells derived from cloned and fertilized blastocysts are transcriptionally and functionally indistinguishable.” Proc Natl Acad Sci U S A. 2006 Jan 24;103(4):933-8. Abstract)
Destroying Embryos, A Moral and Ethical Dilemma with Unanswered Questions
- Since life begins at conception and with cloning there is no conception, can cloned blastocysts therefore be considered human?
- Do the benefits of therapeutic cloning outweigh the moral dilemmas?
These are among the questions at the heart of the bioethical debate. Questions faced by both sides of the aisle. As science continues to progress the previous un-crossable line keeps shifting further away.
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