Stem Cells – Successful Human Cloning Based on Skin Cells Stirs Hope and Controversy

In mid-January 2008, we heard news that scientists at the small private company, Stemagen, in La Jolla, Calif., successfully cloned human embryonic stem cells. Until this breakthrough, human embryonic stem cells had not been successfully cloned. Only other mammals such as sheep, cattle, goats, mice, cats, and dogs had been cloned. We thought human cloning had been accomplished in May 2005 when Korean scientist reported cloning human cells. But his claim was later disproved as other scientists attempted to verify the result.

The details of Stemagen’s success appeared in the Jan. 17, 2008 issue of the journal, Stem Cells. Stemagen scientists inserted the nucleus of a male individual’s fibroblast (skin cell) into an enucleated female egg, then incubated and cultured stem cells from the blastocyst that developed from the artificially fertilized human egg. This success produced stocks of thousands to millions of “toti-potent” stem cells identical genetically to a single individual. These cells can now be the progenitors of all that individual’s different tissues.

Stemagen CEO Samuel Wood, M.D. Ph.D., donated the fibroblasts from which cell nuclei were taken to fertilize the enucleated female egg. Thus, embryonic cells that developed with Dr. Wood’s donated nuclei are clones of his own progenitor cells.

The prevailing concern was that to be successful once, the attempt at cloning would require hundreds of oocytes (eggs) to clone one individual’s stem cells successfully. Stemogen required only 25 donated oocytes to produce five blastocysts fertilized by a cell nucleus from another individual from which stem cells could be harvested and multiplied in culture.

Putting the Controversy into Perspective

Proponents of this stem cell harvesting technology (therapeutic cloning as opposed to reproductive cloning) hope that such autologous stem cells can be used to regenerate diseased tissues in these individuals using their own stem cells. This therapy is envisioned for treating such diseases as Alzheimer’s, Parkinson’s, and Muscular Dystrophy, and for repairing spinal cord injuries without the immune system’s rejecting the tissue. Those against embryonic stem cell research argue against the development of this technology primarily to protect the “sanctity of life” and the right to life of the early-stage human embryo as an individual.

At the center of this debate is the issue of “when does human life begin?” One position is that human life begins with the existence of an egg. A second position is that human life begins with the fertilization of the egg. A third position is that human life begins with the recognition of self. Two years ago, I heard a Harvard stem cell scientist describe the following scenario to illustrate validity of the third position: “Imagine an IVF [in vitro fertilization] clinic that has caught fire and will burn to the ground. There is one person who is left trapped within the burning building along with thousands of fertilized eggs stored in liquid nitrogen tanks. Who will the firemen attempt to save?” The reality is that hundreds of thousands of oocytes are stored in liquid nitrogen tanks that will eventually have to be destroyed if they aren’t used in stem cell research.

Cloned Beings Bring Hazards

Of further concern is the forecast that human beings will be born out of advances of this technology. Several years ago we heard tales of visionaries claiming success within the year with a “cloned baby boy.” No doubt this will be attempted with the likelihood of greater success than cold fusion. If this happens it may be of tragic consequences for the cloned beings who develop genetic errors during the cloning process. Notwithstanding this naïve use of stem cells, potential benefits of therapeutic cloning for the afflicted cannot be ignored. For more details please visit these sites:-

Stemagen scientists state that they have no interest or intent to place these cloned embryos into a woman’s uterus. One wonders how many women would have to be housed to incubate these fertilized eggs to achieve one successful pregnancy. An estimate of at least 300 was floated during the discussion of the fire at the IVF clinic. By contrast about five fusions of somatic nuclei with an enucleated egg (in a petri dish) would generate a therapeutic quantity of stem cells for any individual, according to Stemagen’s finding.

Primary Focus Is on Therapeutic Medicine

Consequently, the goal of Stemagen and many other researchers in this field is to use these autologous stem cells therapeutically by implanting them back into patients to attempt the repair of damaged tissues. No doubt universal acceptance of this medical treatment will take years, and will only come with evidence of success, like in vitro fertilization in the 1970s and recombinant DNA in the 1980s.

There are currently millions of people who could benefit from either direct implantation of autologous stem cells or from the spin-off discoveries of stem cell research. Therefore, I say let’s move forward.


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