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Pluripotent Promises
There may be another way to obtain embryonic-like stem cells.


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Recently the House of Representatives voted, 238-194, to repeal President Bush’s restrictions on federal funding for embryo-destructive stem-cell research, and the Senate is expected to move on a similar bill. Courageously, President Bush has stated that he will veto any such measure. What is at stake is nothing less than fundamental respect for human life. Human embryos are often called by proponents of embryo-killing for biomedical research “mere clumps of cells.” But in fact, from day one on, human embryos are distinct, individual, complete (though immature) human beings, differing from you or me only in size, degree of development, and location. But such differences do not affect the basic kind of being a thing is; such differences are not morally significant.

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Human embryos are not potential human beings, or potential persons. Rather, they are actual human beings, actual human persons, at the embryonic stage of their development. Just as you and I once were adolescents, and before that children and infants, so you and I once were embryos. This assertion is not a religious position the “religious right” attempts to impose on others. Rather, it is the position clearly taught by all the standard embryology and developmental biology texts. You and I came to be at conception. And just as it is wrong to kill one of us now, so it would be wrong to kill one of us at any stage of our development, and wrong to kill any embryo in order to obtain stem cells from him or her.

Human embryo-killing for biomedical research should be illegal, though making it so does not now appear politically possible. But at least taxpayers should not be forced to contribute to such killing through governmental funding of it. This is why the president will be fully justified in vetoing the House’s embryonic-stem-cell bill.

When President Bush announced his intention to veto the House’s embryonic-stem-cell bill, he spoke of researchers’ “exploring different ethical ways of getting the same kind of cells now taken from embryos without violating human life or dignity.” Only adult stem cells have shown significant success in therapeutic uses; to date embryonic stem cells have had no therapeutic success. Still, some scientists say that embryonic stem cells (or pluripotent stem cells at a non-mature stage) have distinct advantages for research. But the good news is that respected scientists from varied backgrounds have proposed a way of obtaining such cells without first creating an embryo and then destroying it. The proposal is to directly produce pluripotent stem cells by a process similar to cloning.

Cloning produces a whole though immature embryo of the species cloned. In this process the nucleus of an oocyte (ovum) is removed; the nucleus of somatic cell with its full set of genes is placed within the enucleated oocyte; an electrical stimulus is provided which somehow knits them together; and what is produced (if the cloning process is a success) is a one-celled embryo of the same species as the somatic cell. This embryo then begins to mature just as a normally produced embryo–so, if humans are cloned this process will immediately produce a distinct human being.

By contrast, a stem cell–that is, a pluripotent cell, one that is relatively undifferentiated, and able to generate many, but not all, more specialized cells–is not a complete organism but is structurally and functionally a part. The proposed process, called Oocyte Assisted Reprogramming (OAR), which is a specific form of Altered Nuclear Transfer (ANT), will directly produce a stem cell. (Dr. Markus Grompe and Robert P. George wrote about this in Monday’s Wall Street Journal.)

The nucleus of a somatic cell will be joined to an enucleated oocyte (as in cloning), but before that, certain genes in the oocyte will be activated, genes that are not normally activated until much later in embryogenesis, at a stage in which the cells have become specialized. The effect of activating (expressing) these genes will be to ensure that the product of the fusion of the somatic cell’s nucleus with the enucleated (and altered) oocyte will be, not an embryo, but a pluripotent cell.

It is a matter of principle that medical progress does not justify any and all means. It is morally abhorrent to dismember living human individuals, no matter what size or degree of development, as a means toward biomedical research or possible therapeutic gains. The end does not justify the means. But here it appears that there may be other equally effective, but ethically upright, means to those same ends. It seems that there will be a way of obtaining embryonic-like stem cells without killing human embryos.

Patrick Lee is a professor of philosophy at Franciscan University of Steubenville.



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