ABOUT STEM CELLS AND CLONING

Editor's note: This guest column is by Gunter N. Franz, who has a Ph.D. degree in physiology and biophysics from the University of Washington. He is an associate professor in the Department of Physiology at West Virginia University School of Medicine in Morgantown, West Virginia. Gunter Franz is the husband of Wanda Franz, Ph.D., president of NRLC.

The House of Representatives recently passed a bill banning the private and public use of human cloning for any purpose. Opponents to the ban protested that the bill would not only ban reproductive but also "therapeutic" cloning, which is the cloning of a new human being for research, medical, or industrial purposes and then later killing him while he is still in the embryonic stage. And that they found unacceptable--the banning, not the killing.

The pro-cloning lobby consists of the Biotechnology Industry Organization (representing 1,000 or more clients), patients' advocacy groups, celebrities who themselves are suffering from serious diseases or have relatives who do, and "progressives" who fear that giving human beings any respect and protection at the embryonic stage undermines abortion rights.

In spite of this formidable opposition, the bill passed 265-162. Supporting the ban were 200 Republicans, 63 Democrats, and 2 Independents--a coalition ranging from conservative Republicans to Socialists. If your representative is one of these, send a note of thanks and encouragement.

Against the ban, that is in favor of creating human beings by cloning and then killing them after they have served someone else's purpose, were 143 Democrats and 19 Republicans. The bill faces a difficult path in the Senate, where anti-life Democrats are in control.

Behind the opposition to the ban is the desire to use cloning for the production of human embryonic stem cells for research and industrial exploitation.

WHAT ARE STEM CELLS?

Eggs and sperm cells (derived from germ cells) are haploid: they have only a single set of chromosomes representing their respective genetic endowment. All other (somatic) cells are diploid: they have a double set of chromosomes. In reproduction, egg and sperm combine, creating a single-cell embryo with a new and unique double (diploid) set of chromosomes (one set each from egg and sperm). A new human being has been formed.

The embryo divides repeatedly to form a cluster of cells. At this very early stage, the cells of the embryo are totipotent, that is they have the potential to develop into any kind of cell type. If the cluster breaks into two separate pieces at this stage of cell division, identical twins are formed because there has been no specialized development of the cells yet.

After a few days, the embryo has developed into a hollow ball of cells with an outer layer that becomes the placenta and promotes implantation into the uterine wall and an inner cell mass that develops into the body of the child.

The cells in the inner layer are pluripotent, that is they can develop into many, but not all, cell types the body requires. At this point, some developmental specialization has already set in. Cells that have the ability not only to reproduce themselves but also give rise to "progenitor" cells (precursors of differentiated cells) and specialized or "differentiated" cells are called stem cells.

As the stem cells divide more, they change from being pluripotent to being multipotent: they become still more limited in their range to develop into various cell types. The ultimate result of repeated cell division is the production of differentiated cells necessary for organ function.

Stem cells are present not only in the embryo but also in the adult. For example, pluripotent stem cells in bone marrow keep up the constant replenishment of red and white blood cells and platelets. Multipotent stem cells in the gut constantly renew the lining of the intestines. Stem cells in the skin produce new skin cells as the old ones are sloughed off. Stem cells in adipose tissue produce fat cells (as some of us know too well), etc.

Given stem cells' ability to produce various cell types, it is no surprise that medical researchers and the biotech industry seek to exploit that potential in order to repair organs by stem cell transplants or generate new ones from such cells. The combination of the pro-choice/"progressive" mindset that considers embryos as disposable entities and the false assumption that adult stem cells are rigidly programmed has led to a massive campaign to allow and publicly fund research on embryonic stem cells. But such research involving the killing of human embryos is morally repugnant and scientifically unwarranted.

A morally acceptable alternative is research on adult stem cells which has shown that (1) they are present in more tissues than previously assumed, (2) many of these cells can be reprogrammed to produce other desired cells, and (3) they may be safer for therapeutic use than embryonic stem cells. (For a long list of references to such research, visit the web site at www.stemcellresearch.org.) While reports of such research have steadily appeared in scientific journals, the popular press has nearly exclusively promoted embryonic stem cell research--the " pro-choice" mentality at work.

CLONING

The transplantation of stem cells into another body leads to rejection of the transplanted cells. Drugs with serious side effects must be administered to suppress the rejection. Hence the desire to find stem cells that have the same genetic make-up as the recipient of the transplant. Using adult stem cells from the ill person's own body would be the answer. But the biotech industry proposes instead to create embryonic stem cells by " somatic cell nuclear transfer." That is how Dolly, the cloned sheep, was created. The idea is to obtain a diploid somatic cell (e.g., skin cell) from the patient's body, take out the cell nucleus which contains a double set of chromosomes and insert it into a human egg cell from which the haploid or single set of chromosomes has been removed. This egg cell has now changed from being "haploid" to "diploid" and subsequently undergoes cell division. The developing embryo is a "clone" of the patient, a genetic twin--except years apart in development. The embryo is specifically created to provide genetically compatible stem cells, the cells are extracted, and the embryonic twin is killed.

This could be very profitable.

It could even help some patients. But it is morally repugnant. You and I must oppose it.