Of all the moral dimensions of stem cell research, the human embryo looms largest1. Recall that viable2
embryos may be created two ways: naturally, through the process of conception, or artificially, through
either nuclear transfer or in vitro fertilization (IVF). In the latter case, removing the inner cell mass
(ICM) in order to produce stem cells destroys the embryo. The cells may survive indefinitely, but the
embryo is gone. Fertilized eggs kept in a freezer or blastocysts grown in a lab will never develop into
a fetus or human because the outer layer of cells, the trophoblast, is missing. Normal development and
a live birth require a viable embryo's successful implantation into the uterus3, where it will grow to
What should we do with leftover embryos from IVF procedures? Are we justified in using them for the
purposes of research? Should we create embryos using nuclear transfer so that we may use them for
therapies? Do we treat embryos the same as a newborn or a child or even as an adult? The moral status
of an embryo - whether we consider it a mere object, a human being, or somewhere in between - is the
subject of thousands of pages of opinion, essays, and research. A rough sorting divides the issue into
two camps. One group believes that embryos deserve protection and should not be used for research. The
other group believes that embryos can be used and embryonic stem cell research should proceed.
The divining rod5 prompting6 each stance is the moral weight given to the embryo.
The blastocyst depicted is shown 330 times larger than life size. lf we place a culture dish under
a microscope and peer at the embryo at this stage, should we protect it from harm?
lf not, should it be used to save others from disability, disease, and death? The debate pivots around
these two questions.
Source: Stem Cell Now by Ch. Th. Scott, A Plume Book, USA, 2006, pp. 126/27
1. to loom large - eine große Rolle spielen
2. viable - lebensfähig
3. uterus - Gebärmutter
4. grow to term - normal weiterwachsen
5. divining rod - Wünschelrute
6. to prompt - veranlassen
1. What is the most controversial question concerning stem cell research?
2. How can embryos be created?
3. At what earliest stage can an embryo grow into a human being?
4. Do you have scruples if scientists use human embryonic stem cells for therapeutic research?
5. Cloning human beings is universally considered as ethically unacceptable. Du you think
that some scientists will eventually try to clone human beings?