The truth about stem cell research
Scientists know that claims of imminent cures of disease using embryonic stem cells are junk science, whereas progress in adult stem cell research has been nothing short of spectacular. It is unfortunate that the mainstream media have exaggerated the prospects for embryonic stem cell research while ignoring the real results achieved with adult stem cells.
Ron Reagan presented a pathetic spectacle at the Democratic convention when he imagined a scenario in the next decade in which a doctor could 'take a few skin cells from your arm,' place the nucleus in a donor egg, zap it with electrical stimulation, culture the cells, and presto 'you're cured.' . But no reputable researcher believes that embryonic stem cells show any promise in the near future of being clinically useful in humans, and success with animals has been minimal. In fact, recent discoveries that some adult stem cells can be turned into any cell type in the body may make discussion of embryonic stem cell therapies moot.
The fact that adult stem cells have already produced remarkable cures, whereas embryonic stem cells have failed in this regard, should not come as a great surprise to anyone with a background in high school biology. When an embryo is created by the union of the sperm and egg, the cells begin to divide, creating embryonic stem cells from which all future tissues and organs are derived. Within days, the embryonic cells differentiate into three cell layers — ectoderm, mesoderm and endoderm. Cells in these layers continue to differentiate into tissues and organs. As the embryo matures into a fetus, child, and adult, some undifferentiated cells of the three types remain in various tissues such as bone marrow, fat, skin and olfactory tissue.
These adult stem cells are multipotent: they have the ability to turn into a variety of types of tissues. Successful stem cell therapies cause the DNA in the adult stem cells to further differentiate into more specific types of cells. There is no point in getting the adult stem cell to turn into a less differentiated type of cell, or using the more primitive embryonic stem cells. This would be going backward, in the opposite direction of providing a clinically useful therapy.
Difficulties abound with proposed embryonic stem cell therapies. The growth of the more primitive embryonic stem cells is more difficult to control and leads to tumor formation. Additionally, the use of embryonic tissue foreign to the patient can potentially lead to problems with immune rejection of tissue, a problem not encountered in using a patient's own adult stem cells. And as Ron Reagan stated, embryonic stem cell therapy is dependent on cloning a 'donor egg,' which is actually a fertilized egg, or early embryo. There would be tremendous logistical difficulty in securing sufficient 'donor eggs' to create useful embryonic stem cell therapies for all the proposed recipients. Most embryos in fertility clinics are slated for use in fertility therapies, and only a tiny percentage are donated for research. In contrast, new sources of adult stem cells are continuously being discovered.
Despite the widespread impression created by some politicians and pundits, the controversial decision by President Bush in August, 2001 did not ban embryonic stem cell research. It merely limited government funding in the US to the 72 embryonic stem cell lines already in existence. Embryos can be destroyed in the process of extracting stem cells. The limitation was put on government sponsoring of research that involved further destruction of embryos. Unregulated embryonic stem cell research continues outside the US, and inside the US with private funding.
Significant scientific problems with embryonic cell research have become more apparent in the past three years, and no useful therapies in humans have emerged. An experiment showed that the use of embryonic cells in mice with Parkinson's led to brain tumors in 20% of the subjects. In another experiment in diabetic mice, embryonic stem cells were successfully converted to insulin—producing cells in the pancreas, but all the subjects died. This contrasts with the full cure of diabetes in mice using transplanted adult stem cells.
Advances in adult stem cell research since Bush's 2001 decision have been nothing short of awesome. At a recent Senate hearing on cutting—edge adult stem cell research, two young women, victims of horrific automobile accidents causing spinal cord paralysis, actually walked into the hearing room. They described their dramatic improvement after spinal cord paralysis. They were treated in Portugal by transplantation of their own stem cells, taken from olfactory tissue that has the ability to form new nerve cells.
In Germany, a cancer victim whose jaw had been removed re—grew bone tissue utilizing adult stem—cells from his own bone marrow, and was able to eat a bratwurst sandwich for the first time in nine years. Patients with Parkinson's disease have reported significant improvement, some even regaining their sense of taste and smell, with injections of GDNF, an adult stem cell related therapy. A recent PBS special recounted other significant human cures with adult stem cells, and a Texas surgeon liposuctioned himself to promote excess fat as a viable source of adult stem cells. Do No Harm, the web site of a coalition of American scientists for ethical research, is replete with dozens more successful examples of cures from adult stem cell research.
Senator Jon Corzine has donated $100,000 to help pass Proposition 71 in California, which would force Californians to borrow $3 billion over 10 years to help biotech companies to conduct mass experiments on embryonic stem cells. This dwarfs the few million dollars that the infamous New Jersey Governor James McGreevy prodded its legislature to throw to biotech companies for embryonic stem cell research and cloning .
However, the private sector has refused to invest in this type of research because it is unlikely to provide useful products any time soon. Jim Kelly, a Colorado stem—cell activist who is a paraplegic, agrees with private venture capitalists and says, 'We have to use our limited resources efficiently. Money spent on embryonic stem cell research and human cloning is money that cannot be spent on (investigating) adult stem cells.'
In addition to practical arguments against embryonic stem cell research, there are serious moral and ethical arguments. The destruction of embryos in research is the destruction of human life, a line that should never be crossed by researchers. A recent poll has shown that Americans strongly prefer funding research that does not destroy human embryos.
Yet another reason has emerged why there is incessant pressure for embryonic stem cell research, despite mounting evidence of its inferiority to adult stem cell research, in testimony before a Senate Committee on July 14, 2004. After discussing the cases of the two paralyzed young women who were now walking after adult stem cell treatment in Portugal, Dr.Jean Peduzzi—Nelson pointed out that an embryonic stem cell product could become patentable and potentially yield enormous profits. But an adult stem cell therapy, in which the patient's own cells were used, could not produce a patentable procedure or product according to current laws.
It would be tragic if political considerations and greed diverted funding away from fruitful lines of research utilizing adult stem cells, which show promise in producing the cures sought by so many desperate patients.