STEM CELL ADVANCES AND THE VALUE OF THE HUMAN EMBRYO

• First, a summary of the findings.  Chinese scientists have bred mice from cells that might offer an alternative to embryonic stem cells, producing the most definitive evidence yet that the technique could help sidestep many of the explosive ethical issues engulfing the controversial field.  However, this advance could also raise some alarm that the research could lead to human cloning and “designer babies.”  In papers published in late July, in two scientific journals (Nature and Cell Stem Cell), separate teams of researchers from Beijing and Shanghai reported that they had for the first time created virtual genetic duplicates of mice using skin cells from adult animals that “had been coaxed in the laboratory into the equivalent of embryonic stem cells.”  The procedure, announced in the above named journals, summarizes that the researchers used viruses to “flip genetic switches in the DNA of skin cells from adult mice to turn them into iPS [induced pluripotent stem] cells into very early embryos that are capable of forming a placenta but not fully developing on their own.  The resulting embryos were then transferred into the wombs of female surrogate mice.”  One team of scientists produced 37 iPS lines, three of which produced 27 offspring.  Rob Stein, Washington Post reporter, summarizes that “Altogether, the researchers bred at least 100 first generation mice and hundreds of second generation mice that were nearly identical genetically to the mice from which the iPS cells had been derived.”  This research currently demonstrates that embryonic stem cell research is not needed.  However, the danger of this research is that it could actually enhance the technology for reproductive cloning and could enhance research to produce an era of “designer babies” by enabling researchers to genetically engineer traits into cells using them to create embryos.  In short, the ongoing stem cell research is rather frightening.  This new research validates that embryonic stem cell research is not needed to accomplish the goals of genetic technology.  However, as with all kinds of research in this area, there are unintended consequences—we could solve the embryonic stem cell debate but actually enhance something equally as troubling.

• Second, we must probe the question, does the human embryo have moral value?  Ethicist Michael Sandel probes the motive behind genetic and reproductive technology research:  “In a world without givens, a world controlled by bioengineering, we would dictate our nature as well as our practices and norms.  We would gain unprecedented power to redefine the good. . . The more successfully we engineered IQ and muscle-to-fat ratio, the more central these measures would become to our idea of perfection.  We already see this phenomenon in our shift of educational emphasis from character to academic testing.  We might create a world of perfect SATs, ERAs and CEOs.  But it would never be a perfect world. . .”  (Michael Sandel, The Case Against Perfection: Ethics in the Age of Genetic Engineering.)

Reproductive and genetic technologies have empowered humans to a degree unimaginable only a few years ago.  These technologies are also empowering parents to decide what kinds of children they want.  Therefore, these technologies raise profound ethical questions, including ethical questions about the human embryo.  We cannot ignore them.  Here are some practices that raise profound ethical questions:

1.  THE USE OF DONOR EGGS IN INVITRO FERTILIZATION (IVF)

• Used in 12% of all IVF cases
• The result is the mind bending phrase, “bio-genetic child,” meaning a child who is both biologically and genetically related to each of its parents, but, for the first time in history, separating those components.
• Ethical Questions:
• 1.  Should the woman who donates her eggs be paid?
• 2.  Should we accept the practice of selling eggs with specific personal attributes in mind?
• 3.  Should we permit parents (or other mothers) to choose the person they want to donate the eggs?
• 4.  Should the basis be IQ, appearance, heritage or race?
• 5. Are we getting close to eugenics if we, as a civilization, permit this?
• 6.  Do the children of such a procedure have the right to know that the egg which was fertilized is not the egg of their mother who raised them?
• 7.  Should there be “open-identity” donation procedures? 
• 8.  Should we, as a civilization, provide opportunities for children to establish a relationship with their donor egg mother or donor sperm father?

2.  PREIMPLANTATION GENETIC DIAGNOSIS (PGD)
Through IVF, eggs are fertilized and allowed to divide for 3 days (at the 8-cell stage).  The cells of the embryo are tested for defective genes carried by the mother or father.  Embryos free of defective genes are then implanted in the mother’s uterus or frozen.

Ethical Questions with PGD:

• Is it wise to allow widespread use of PGD?  (It is currently used in about 10% of IVF procedures in the US.)
• Could PGD be used to determine other traits or characteristics?  Could it become a tool in fact for eugenics?
• Should there be limits to the empowerment of parents using PGD?
• Who would set those limits?

3.  CYTOPLASMIC HYBRID EMBRYOS
Recently, the UK’s Human Fertilization and Embryology Authority cleared the production of cytoplasmic hybrids for stem cell research.  The nucleus of an animal ovum is replaced with human DNA, producing an embryo that is 99.9% human.

Ethical Questions:

• Does such a procedure violate a deeply ingrained principle of “species distinction” between      humans and animals?  Is there a “creation-order distinction” being violated here?
• Do “interspecies embryos” pose a slippery slope of unintended consequences?
• Does this procedure challenge human dignity?

4.  CONSIDER: LIFE AS A CONTINUUM
“Human development begins at fertilization, the process during which a male. . . sperm unites with a female [egg] to form a single cell called a zygote.  This highly specialized, totipotent cell marked the beginning of each of us as a unique individual.  [A zygote is defined ] “as the beginning of a new human being.”

“Although most developmental changes occur during the embryonic and fetal periods, some important changes occur during later periods of development: infancy, childhood, adolescence, and adulthood.  Although it is customary to divide human development into prenatal (before birth) and postnatal (after birth) periods, birth is merely a dramatic event during development resulting in a change in environment.  Development does not stop at birth.” 

Moore, Keith L. and Persaud, T.V.N.  The Developing Human: Clinically Oriented Embryology.  6th edition. Philadelphia: W.B. Saunders Company, 1998, pp. 2 and 18.

A PLEA:
At the very least, human civilization must have a conversation about the ethical implications of the procedures discussed in this Perspective.  As a part of the conversation, I believe we should also revisit the ethical value of the human embryo.  As a Christian, I believe that the human embryo does have ethical and moral value.  At least Psalm 139:16 is a starting point for our thinking about the value of the human embryo.  This verse indicates that God assigns the human embryo infinite value.  So should we!

See Rob Stein’s article on the Chinese research on stem cells in the Washington Post (23 July 2009). 

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