MEDIA BIAS is alive and well and busily promoting the brave new world. I personally experienced the phenomenon recently when I participated in an educational symposium in Frankfort, Kentucky (along with Drs. David Prentice and John Hubert). Our purpose was to provide empirical and moral support for pending state legislation that would outlaw human cloning in Kentucky. (Similar laws have already passed in Michigan, Iowa, North Dakota, and Arkansas.)

We spoke about regenerative medicine (using cellular treatments to repair injured or damaged organs), the science of human cloning (how mammalian cloning is accomplished), and the crucial moral issues raised by cloning humans, such as the potential consequences of treating the creation of human life as a matter of mere manufacture.

We also spent a great deal of time discussing the many advances being made in using adult stem cells as efficacious and morally non-controversial sources for regenerative medical treatments. Indeed, we devoted nearly one third of the more than two-hour event to contrasting the many exciting adult stem cell research breakthroughs compared with the relative paucity of embryonic stem cell successes and the virtually non-existent advances in therapeutic cloning research.

Adult stem cell therapy would be almost magical. (A good analogy might be the common practice of donating your own blood for later use in your own surgery.) Instead of taking drugs to treat degenerative ailments such as Parkinson's disease or undergoing organ transplant surgery, if adult stem cell therapy works the way researchers hope, doctors would be able to harness the patient's own

EMBRYONIC STEM CELLS are another potential source for regenerative treatments. But, we pointed out, unlike adult stem cell treatments, ES cells cannot be used in human studies because of two fundamental safety issues. First, they cause tumors in animal studies. For example, in one recent experiment, ES cells were injected into a mouse in the hope they would rebuild the animal's damaged knee. Instead, the cells obliterated the knee by stimulating tumor growth. (More recently, an adult stem cell animal study successfully rebuilt joints without causing tumors.)

Second, using embryonic stem cells as a regenerative treatment--unlike adult stem cells--would introduce foreign tissues into the patient, perhaps stimulating the immune system to reject the tissues. "Therapeutic cloning" is supposed to get around this problem. The complicated procedure would involve the manufacture of cloned embryos of the patient who is to receive the stem cell treatment. The cloned embryos would be developed for one week to the blastocyst stage. At that point, they would be destroyed, and their embryonic stem cells harvested. (To date, researchers have been unable to successfully create cloned human embryos to the blastocyst stage.) These would then be proliferated in culture and eventually injected into the patient, the hope being that the tissues would not be rejected because the DNA from the cloned embryo and that of the patient would be nearly identical.