Thursday, June 07, 2007

Meisner in Wonderland

“When I use a word,” Humpty Dumpty said in rather a scornful tone, “it means what I choose it to mean – neither more nor less.”

Rep. Andrew Meisner (D-Ferndale) was on the WJIM morning show yesterday promoting his bill to legalize embryonic stem cell research in Michigan. He didn’t say “embryonic,” though; he said “pre-embryonic.” I hadn’t heard this before and figured that it had been made up. I was correct; a frog embryologist came up with it in 1979 with the intent of devaluing the status of human embryos. See below.
*Note, despite what you might think, this research is legal Federally. The Feds just don't fund it.

Meisner went on to describe how these “clumps of cells” would provide cures for Alzheimer’s, Parkinson’s and Juvenile Diabetes. Appropriate references to the suffering of those so afflicted were not in short supply.

He lambasted “the opposition” for being opposed to creating jobs by rejecting such research, and lamented Michigan’s stifled innovation.

Even if it were demonstrated that the terrible diseases listed would be cured, which it is not, it does not change the basis of the debate. That is an ethical question, not one of the need of others and not an economic one. Otherwise, we’re into the Soylent Green scenario. Otherwise, why not start an industry that makes souvenirs out of human skin? That’s already been tried, and it is, therefore, possibly not innovative enough for Rep. Meisner, and t
here's also the fact that it didn’t end well for the manufacturer.

Meisner simply ignored the question of to what purpose one human organism may be sacrificed to the needs of another human organism. If you assume automatically that embryos are not human, you can say that sort of thing. However, that is precisely the definition of “begging the question.”

Using pseudo-scientific words, arguing that job creation is in the same ethical universe as using human embryos in research and touting the health benefits to post-embryo persons, all ignore the actual question.

“Pre-embyronic” strikes me as Orwellian. Following is some commentary about the term.

Cloning: Redefining When Life Begins Exposing Flaws in the Preembryo-Embryo Distinction
by Kelly Hollowell, Ph.D.

…The Ethics Committee [of the American Fertility Society] explains differentiation in terms of "development of an individual" as correlated with visually recognizable structures of the developing embryo, and described in terms related to twinning (the splitting of an embryo into two identical twins). Specifically, the committee reports that, "[w]ith the appearance of the [primitive] streak, as far as is now known, the embryonic disc is committed to forming a single being; beyond this point, twinning is not believed to occur, either naturally or experimentally" (vol. 53, #6, at 32s, June 1990). Therefore, absent specific visually recognizable structures that indicate an end to the embryo's ability to create a twin, a human embryo is not a person nor is it property. It is a preembryo. There are at least two recognizable flaws in relying on this explanation as a basis for defining the preembryo status.

First, while it is conceded that prior to 14 days, single embryos have the ability to split or be split to effect development of more than one independent adult, each life so created develops in exactly the same manner as the embryo from which it was split. This is the result of being derived from the exact same genetic material. This event merely serves to reset the biological clock of the embryo, forcing it to repeat previously experienced divisions. In humans, this event does not prevent the embryo from attaining eventual personhood. At a minimum, the embryo will develop into at least one life. It is questionable, therefore, whether the phenomenal ability of the embryo, under some conditions, to produce more than one life should diminish an embryo's life status.

Second, evidence that the embryo is a specific life from the moment of conception is actually offered by cloning technology. The moment that a complete set of 46 chromosomes is introduced into an enucleated egg, the embryo is a very specific life, identical to the donor of the genetic material. To illustrate, the success of Dolly and various other cloned animals provides undeniable evidence that the embryo is set on a predetermined pathway of life from the moment the complete set of chromosomes is introduced into the egg. That is precisely the science and logic that explains how the clonal embryo is capable of duplicating the donor.

The individual cells of the clonal embryo early in cleavage follow the exact path of development followed by the donor of the genetic material when the donor was embryo. In other words, there appear to have been no options for the clonal embryo, as a whole, in its development. Therefore, we can infer that there were no options for the initial groups of cells (the preembryo) that came into existence through cell division in the first few days of life. Recalling that the moment that a complete set of chromosomes is introduced into the egg is equivalent to the point of conception, it is clear that development of the "individual" is encoded in the genetic material itself, and does not require 14 days to be committed to forming an individual being.

Additionally, differentiation is explained by the committee report in terms of uterine implantation. The report states that it is the physiologic interaction of the embryo with the mother during implantation that determines the path of differentiation. Clearly, cloning suggests otherwise. Specifically, the clonal embryo develops in exactly the same manner as the donor, despite the absence of the same available womb. Cloned animals, such as Dolly, were not implanted into the womb of the same mother that birthed the donor of the genetic material. Yet, the clonal embryo was a genetic duplicate of the donor. Therefore, it is not the physiologic interaction of the embryo with the mother during implantation that determines the path of differentiation. Implantation of the egg in the uterine wall merely provides the nutritive environment for continued growth in relation to the embryo's current stage of life.

With these points in mind, one must recognize that the scientific rationale behind the preembryo-embryo distinction is flawed. The logic and specific evidence provided by successful cloning experiments indicates strongly that both the clonal embryo and the fertilized egg have been set on the path of life, not a path destined for life, the moment that the complete set of chromosomes exists within the cell. Indeed, if there is a preembryo, then it is the egg and the sperm themselves, not the clonal embryo or the fertilized egg. As a result, this analysis suggests that the human embryo, even at the very earliest stages, should be recognized as protectable life. This requires that the embryo be accorded the rights of a person: according to the committee report, "this position entails an obligation to provide an opportunity for implantation to occur and tends to ban any action before transfer that might harm the embryo or that is not immediately therapeutic."
I admit I am unable to follow the logic of considering whether or not an embryo might split as an essential part of the definition of human life. If it is possible you are terminating two or more individuals, genetic or otherwise, instead of one - that solves your ethical dilemma how?

See also: The ‘Pre-Embryo’ Question
By Dr. John B. Shea M.D.

In 1979, Clifford Grobstein, a frog embryologist, coined the word “pre-embryo.”1 He subsequently admitted that the word was conceived in order to reduce the “status” of the early human embryo, whom he declared to be a “ pre-person.”2 He held that since identical twins may occur up to fourteen days after fertilization, only a “genetic individual” is present, not a “developmental individual”, and that therefore an embryo, a “person”, is not present.3 This notion of a “pre-embryo” was also supported in 1979 by the bioethics writings of Jesuit theologian Richard McCormick, in his work with the Ethics Advisory Board to the United States Department of Health, Education, and Welfare.4

“The terms ‘pre-embryo’ and ‘individuality’ have been totally discredited, by all Human Embryologists, and have also been rejected by the Nomenclature Committee of the American Association of Anatomists for inclusion in the official lexicon of Anatomical Terminology, Terminologia Embryologica. These terms are not used in any official textbook of Human Embryology.”5 They are also not used in the Carnegie Stages of Human Early Development. The scientific evidence indicates that from the moment when the sperm makes contact with the oocyte (ovum), human development is an integrated continuum in which one stage follows another throughout all of life until death, and therefore that the developing human being is both a ‘genetic’ and a ‘developmental’ individual from the first moment of its existence.
The point of this definitional struggle is actually not the partitioning of the continual and seamless development of a zygote into more scientifically accurate, discrete phases; it is an attempt to subvert discussion about foundational moral and ethical concepts. Creating new terminology is merely an attempt to hijack the debate.

A zygote is what you have immediately upon conception, a single cell composed (in humans) of an ovum from a female and a sperm from a male. The full human genotype of an individual is already established at that point. Immediately upon the first cell division, for all placental mammals except humans, the embryo is defined by the first cell division. In humans, the zygote is not legally defined as an embryo until implantation into the uterus, 5-7 days after fertilization. As you can see, while we already apply different definitions to human reproduction than we do to other like animals, “pre-embryo” is meant simply to re-redefine what it means to be human.

Since the 14 day period described as “pre-embryonic” overlaps with the 5-7 days defined by the scientific standard term embryonic, the former term can be seen as useless and misleading.

If the discussion is about the moral slippery slope we edge out upon by experimentation on human embryos, that’s as it should be. If, instead, we’re treated to invented words, statements that those who have certain diseases are entitled to the use of human genetic material and an appeal to decreasing unemployment, that’s devious and disgusting.

Here's the regenerative medicine innovation Michigan could have been pursuing all along. From today's New York Times: Biologists Make Skin Cells Work Like Stem Cells. It doesn't get any more "pre-embryonic" than that.

In a surprising advance that could sidestep the ethical debates surrounding stem cell biology, researchers have come much closer to a major goal of regenerative medicine, the conversion of a patient's cells into specialized tissues that might replace those lost to disease.

The advance is an easy-to-use technique for reprogramming a skin cell of a mouse back to the embryonic state. Embryonic cells can be induced in the laboratory to develop into many of the body*s major tissues.

If the technique can be adapted to human cells, researchers could use a patient's skin cell to generate new heart, liver or kidney cells that might be transplantable and would not be rejected by the patient's immune system. But scientists say they cannot predict when they can overcome the considerable problems in adapting the method to human cells.

..."From the point of view of moving biomedicine and regenerative medicine faster, this is about as big a deal as you could imagine," said Irving Weissman, a leading stem cell biologist at Stanford University, who was not involved in the new research.

David Scadden, a stem cell biologist at the Harvard Medical School, said the finding that cells could be reprogrammed with simple biochemical techniques "is truly extraordinary and frankly something most assumed would take a decade to work out."

The technique seems likely to be welcomed by many who have opposed human embryonic stem cell research. It "raises no serious moral problem, because it creates embryonic-like stem cells without creating, harming or destroying human lives at any stage," said Richard Doerflinger, the United States Conference of Catholic Bishops'
spokesman on stem cell issues. In themselves, embryonic stem cells "have no moral status," and the bishops' objections to embryonic stem cell research rest solely on the fact that human embryos must be harmed or destroyed to obtain them, Mr. Doerflinger said.

Ronald Green, an ethicist at Dartmouth College, said it would be "very hard for people to say that what is created here is a nascent form of human life that should be protected." The new technique, if adaptable to human cells, "will be one way this debate could end," Mr. Green said.

...In articles published today in Nature and a new journal, Cell-Stem Cell, the three teams show that injection of the four genes identified by Dr. Yamanaka can make mouse cells revert to cells indistinguishable from embryonic stem cells. Dr. Yamanaka's report of last year showed that only some properties of embryonic stem cells were attained.

This clear confirmation of Dr. Yamanaka's recipe is exciting to researchers because it throws open to study the key process of multicellular organisms, that of committing cells to a variety of different roles, even though all carry the same genetic information.
Maybe it's Rep. Meisner who has not been innovative.

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