The two papers published online this week by Nature highlighted what proponents of embryonic stem-cell research like to call “ethical alternatives.” Sadly, they were not talking about the 600-pound gorilla in the room called adult stem-cell research, which is successfully treating 65 different human diseases. They were instead talking about two very convoluted methods used by researchers to take the body parts of very early embryos without technically destroying them in the process.
In one case, researchers Rudolf Jaenisch and Alexander Meissner of the Whitehead Institute in Cambridge, Mass., describe a procedure called “altered nuclear transfer,” or ANT. In this procedure, they turn off or “knock out” the genes necessary to form the trophoblast. That is the essential part of a developing embryo needed to implant in the mother’s womb. So by creating an embryo that is incapable of implanting, proponents claim they have sidestepped the ethical dilemma.
Let me get this straight. You have genetically disabled the embryo so it will have no chance to implant and thrive. This makes human experimentation and sacrifice of this embryo OK?
Hmmm … sounds to me like the macabre experiments done years ago by scientists who created a headless frog to use its body parts. Supporting this analogy, one of the leading proponents of this method is quoted as saying that embryos created in this manner “have no moral status. They are the equivalent of a brain dead embryo.”
Forgive me if I fail to see this as an ethical alternative. In essence you are deliberately creating a disabled embryo, then claiming its disabilities are the very justification needed to sacrifice the embryo for its stem cells.
Wait, maybe it will help if I say it another way. ANT intentionally creates a genetically defective embryo using human cloning techniques to create embryonic stem cells for research.
No. That didn’t help. Let’s move to the next “ethical alternative.”
In this set of experiments, a team of scientists led by Robert Lanza of Advanced Cell technology in Worcester, Mass., plucked single cells called blastomeres from eight-cell embryos. The single cell was plated in a Petri dish to grow stem cells. The remaining seven-cell embryo was implanted. In the Nature report the experiments were done on mice. Roughly half of the implanted embryos came to term.
So what’s wrong with this procedure, once again ignoring the 600-pound gorilla in the room called adult stem-cell research? Where shall I begin?
First, consider that it is quite possible that the extracted blastomere itself could develop into a fully functioning embryo. This is a phenomenon known as twining, and it’s been around naturally since the beginning of time; in the lab for years. So a potential life may still be sacrificed to obtain the embryonic stem cells.
Next consider that the resulting stem cells created from this isolated blastomere could only come from couples undergoing IVF, thereby limiting the usefulness and wide scale application of stem cells harvested in this way.
These stem cells could, of course, be used without fear of immune rejection by the remaining seven-cell embryo if he or she were implanted and made it successfully to full term. But right now there is only about a 50 percent chance of that even in mice.
By the way, what woman having trouble getting pregnant in the first place seeks professional help, then subjects her embryos to trauma so great as to reduce the odds of actually having a healthy baby? Oh, that’s right, those people obsessed with themselves and perfection. That brings me to my next point.
Consider that this second method is closely associated with preimplantation genetic diagnosis, or PGD, in which parents concerned about having a child with any genetic disability have their IVF-created embryos tested or screened before deciding to implant and bring these very young lives to term.
This procedure has been in practice in IVF communities for about 10 years, which means we know in the short term this procedure is successful. What we don’t know is the long-term effects of this technique. Even now, controversy rages about standard IVF procedures and the long-term effects on the health of the individual conceived by this process.
For example, over the last five years there have been a number of conflicting reports regarding the increased risk of IVF babies to various defects and cancers. Most notably a Dutch study found a link between retinoblastoma, a childhood cancer of the retina, and IVF. These results came one week after a British study reported IVF children were at five times the risk of a rare genetic disorder, Beckwith-Wiedemann syndrome, characterized by large body size and tumors.
The New England Journal of Medicine reported that infants conceived by IVF procedures have twice as high a risk of major birth defects as naturally conceived infants. And just last year, two doctors from Cornell University confirmed the increased risk of IVF babies to Beckwith-Wiedmann syndrome as well as Angelman’s syndrome, which is associated with mental retardation and a near-total lack of speech.
But I digress.
Returning to the proponents’ claim that these Nature articles and experiments provide “ethical alternatives” to ESCR, both ANT and PGD-related procedures for creating embryonic stem-cell lines run afoul of the Dickey Amendment. This amendment absolutely prohibits federally funded research where human embryos are destroyed, discarded or subjected to substantial risk. That means even if these procedures were the magic bullet ESCR proponents seek, our tax dollars cannot fund them.
All said these two “new answers” to the ethical dilemma surrounding ESCR provide no answers at all. One disables the embryo through genetic engineering that is then coupled with cloning (ANT). The other (PGD) is a twist on a mere 10-year-old artificial reproduction technique that is not only used to screen out who is worthy of a shot at life but also pushes the envelope in an area of research that is already mired in controversy over its long-term risks to human life. Furthermore, PGD-related experimentation raises the question of whether the cell plucked out of the very young embryo is also a potential life destroyed in the process of isolating embryonic stem cells.
Finally, let’s not forget that all tolled, when comparing adult stem-cell therapies to embryonic stem-cell therapies, the count is still 65-0.