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Human Exceptionalism

Life and dignity with Wesley J. Smith.

Embryonic-Like Stem Cells Not Embryos



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Principles matter to pro lifers. They really believe in the sanctity of each individual human being from conception until natural death. And they try to promote public policies and live their lives (imperfectly, to be sure) in accordance with their beliefs.

The mainstream media and mavens of popular culture often mistranslate pro life concern into ”judgmentalism” and “hatred”–and it is true that some pro life communicators sometimes come across as holier than thou. But pro lifers really want to do the “right” thing as they perceive the right. That’s admirable.

This concern for principle explains why the movement has been involved in an internal debate about the biological nature of induced pluripotent stem cells–that is stem cells made from human skin. Some have worried that IPSCs might actually be embryos or capable of becoming embryos, rather than mere cells. The cause of the concern is chemical marker known as an “antigen” found on the stem cells that are also found in actual embryos.

My smart friends Drs. David Prentice and Maureen Condic investigated the question and have now assured pro lifers that the process does not create embryos. It’s an arcane discussion that requires some biological knowledge.

- Totipotent means that a cell is or is capable of developing into the whole organism.

- A one-celled embryo, known as a zygote, is an example of a totipotent cell.

Pluripotent means capable of becoming any type of cell. For example, a pluripotent stem cell can be changed into a brain cell or a heart cell. But it isn’t–nor can it become–an organism.

Ditto, an embryonic stem cell–which are not unethical because they are embryos, but because they are derived by destroying embryos.

With that in mind, here is the bottom line. From, the Life News.com article:

If a molecule was discovered that was normally only expressed by human zygotes or early stage totipotent cells of the human embryo, and this molecule was also expressed by some types of stem cells, this still would not “prove” that these stem cells were embryos, but it would raise some concern. However, this concern definitely does not apply to [the antigen]  Lewis-X/CD15/SSEA-1, which is not expressed by totipotent human embryos, and is expressed by many specialized adult cell types.

Don’t be misled by the simple fact that for historical reasons one of the names of this common antigen happens to include the word “embryonic.” Expression of this antigen by some human stem cells does not make them human embryos.

In other words, at least as to this aspect of the issue, IPSCs are ethical.

It’s ironic. Many among the intelligentsia urge that we live “the examined life.” Yet, when pro lifers do just that, they are mocked.

But at least they think that principles really matter. Which is why they care about accurate biology as the necessary predicate to properly applying their ethical concerns. 



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