The Genetics of Ensoulment
What's an embryo and what's not?
Ronald Bailey | May 13, 2008

Until about a decade ago, there was only one way to make an embryo-the 
old-fashioned technique of combining an egg with a sperm. Then came Dolly 
the cloned sheep in 1996. Scottish scientists created her by injecting the 
nucleus of a breast cell from one sheep into the enucleated egg of another 
sheep. Dolly was essentially genetically identical to the donor of the 
breast cell nucleus.

Since then researchers have used reproductive cloning to produce mice, cats, 
dogs, horses, cows, goats, pigs, and other mammals. As valuable as 
reproductive cloning is for producing livestock and research animals, most 
researchers were excited by the prospect of using cloning to create human 
embryonic stem cells. These stem cells produced by therapeutic cloning might 
be used to grow perfect transplants to replace and repair damaged tissues 
and organs.

Therapeutic cloning to produce transplants fell directly into the heated 
abortion debate. From the pro-life point of view, cloned human embryos, like 
all other embryos, have the same moral status as adult human beings. The 
moral status of five-day embryos is still contested. Hoping to avoid 
controversy, researchers searched for sources of cells that would have the 
valuable properties of embryonic stem cells (self-renewing and transformable 
into any type of cell), but would be acceptable to pro-lifers.

One proposal is to create human stem cells using altered nuclear transfer 
(ANT). Championed by Stanford University bioethicist William Hurlbut, the 
technique is essentially the same as regular cloning except that it uses RNA 
interference to disable a single crucial gene so that the cloned entity 
cannot implant into a womb and thus cannot grow into a fully developed 
embryo. In ANT all of the genes involved would be human, even the one that 
has been deliberately broken.

A number of prominent Roman Catholic thinkers recently endorsed ANT as a 
morally acceptable way to produce human embryonic stem cells. So whether or 
not an entity can house a human soul evidently depends on the timing of the 
operation of a single gene. Other theologians question this, asking why such 
a cloned entity should not be considered a defective human embryo deserving 
of same the moral solicitude owed to disabled adult human beings.

The search for a morally unproblematic source of stem cells continued. Last 
fall, Shinya Yamanaka and his colleagues at Kyoto University in Japan and 
another team at the University of Wisconsin announced the good news that 
they had been able to transform adult human skin cells into cells that act 
very much like embryonic stem cells. Yamanaka took skin cells and inserted 
four genes-Oct4, Sox2, Klf4 and Myc-that are expressed in embryonic stem 
cells, causing the skin cells to revert to the embryonic state. These 
induced pluripotent stem (iPS) cells are generating a huge amount of 
excitement among stem researchers and were even hailed as the end of the 
stem cell wars.

Well, not quite. The Kyoto and Wisconsin researchers used skin cells 
originally derived from human fetuses in their research. Still, such cells 
are not necessary to generate new iPS cells; they were just convenient. But 
let's approach the moral issue from another direction.

It turns out that, at least in mice, injecting iPS cells into mouse 
blastocysts creates chimeric mice. The iPS cells are incorporated into the 
developing mouse embryo and form part of the tissues and organs of new mouse 
pups. Researchers at the Whitehead Institute in Massachusetts have gone even 
further. They created a mouse comprised entirely of iPS cells. The iPS cells 
form an embryo after they are embedded into tetraploid embryonic cells that 
grow into a placenta. There is no apparent reason why this technique 
wouldn't work in humans.

In April, this insight caused The Independent to hyperventilate, "Now we 
have the technology that can make a cloned child." The Independent quotes 
stem cell researchers Robert Lanza: "It raises the same issues as 
reproductive cloning and although the technology for reproductive cloning in 
humans doesn't exist, with this breakthrough we now have a working 
technology whereby anyone, young or old, fertile or infertile, straight or 
gay can pass on their genes to a child by using just a few skin cells." 
Maybe so, but iPS cell research raises an even more intriguing question.

Back in 1999, during a hearing of the National Bioethics Advisory 
Commission, then-Director of the National Institutes of Health Harold Varmus 
made the intriguing observation that "It may eventually become possible to 
take a cell from any one of our organs and to expose it to the right set of 
environmental stimuli and to encourage that cell to return to a more 
primitive stage in the hierarchy of stem cells. Under those conditions, one 
might in fact generate the cell with as great a potential as a pluripotent 
cell from a very mature cell." Nine years later Yamanaka proved that Varmus 
was prophetic.

Varmus continued, "One might even in fact imagine generating a cell that is 
totipotent [able to develop into a complete organism] in that manner." In 
other words, researchers may one day take human cells all the way back to 
the embryonic stage, at which point they could be implanted into a womb, 
where they could eventually develop into complete human beings. This is the 
direction in which iPS cell research is heading. So instead of switching off 
one gene to make sure that an entity is not worthy of their moral concern, 
pro-lifers may soon have to worry about the opposite, pushing an adult cell 
so far back in its developmental stage that switching on a single gene will 
turn it into an embryo.

Advances in stem cell research may be provoking a kind of "God of the Gaps" 
retreat on the moral status of embryos. People who subscribe to God of the 
Gaps thinking believe that the hand of God can be seen in those things which 
science cannot explain. In this case, the closing gaps in the details of 
molecular biology are forcing pro-lifers into an uncomfortable corner where 
they have to decide whether or not a cell can be imbued with a soul by 
turning a single gene on or off.

Rayilyn Brown
Board Member AZNPF
Arizona Chapter National Parkinson Foundation
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