Stem cell politics. (Trends).

It's a scary thing to find yourself in bed with Orrin Hatch. I've always believed that principles must inform political ideology, and not the other way around, even if that brings you unexpected political bedfellows. But Sen. Hatch? I don't even own a gun. So why do we agree (in part) on stem cell research?

First, a quick primer. Stem cells are "blank" cells that have the potential to develop into any type of cell in the body--nerve cells, heart cells, kidney cells. Scientists are trying to harvest the cells before they have differentiated, then coax them into becoming specific types. If they could grow cardiac cells, for instance, scientists one day might be able to replace damaged heart tissue in someone who has a heart attack. By growing nerve cells they might be able to repair brain cells damaged by Alzheimer's or Parkinson's, or replace injured spinal cord cells in a paraplegic.

Where are scientists getting these cells? The vast majority of stem cells used in research came from discarded (or excess) embryos--stored at in vitro fertilization clinics--that have never seen the inside of a woman's uterus. Once an infertile woman has successfully birthed a child, then she and her partner may be asked to donate the unneeded embryos for research. Scientists can also pull stem cells from aborted fetuses, asking for signed consent from a patient who had independently decided to terminate her pregnancy. As opponents of stem cell research are quick to point out, there are other ways of culling the precious cells extracted from the umbilical cord, bone marrow cells, or even cells from fat tissue, but unfortunately none of these methods yield stem cells with the same vitality and versatility as those taken from embryos.

THE PUBLIC DEBATE is heated. On the one hand you have celebrities like Christopher Reeve and Michael J. Fox who see stem cells as at potential cure for their maladies, and on the other side you have people who say no cure is worth destroying a human embryo. Unfortunately, our cultural civil war immediately polarizes all issues dealing with reproduction and genetics, making casualties out of the legitimate concerns expressed on both sides of the debate.

So I don't expect my own three benchmarks will please anyone entirely. But I'll toss them up for target practice anyway

1) We are compelled to end suffering. While there are no guarantees of positive results, stem cell research represents the best hope to find cures for some of the most debilitating diseases facing us. Life does not begin at conception and end at birth. Slotting this :issue neatly into an abortion box does not fit.

2) Not all stem cells are created equally. Too many researchers limit truth to measurable results. For them, a stem cell is a stem cell. But outside of the lab, we respect human identity. Experimenting with stem cells from aborted fetuses is no different from experimenting on a child who has died in birth. Would we approve of the latter? I don't think so.

3) A test tube is a medical instrument, not "potential conception." If you already support in vitro fertilization, then you have no ground for opposing the harvesting of stem cells. It is exceptionally rare for an infertile couple to make use of all the embryos that result from the procedure. The rest are eventually discarded. As my ally Orrin Hatch (shudder--I was hoping it would sound better the more I used it) says, "Why shouldn't embryos slated for destruction be used for the benefit of humankind?"

We are facing only the first wave of moral dilemmas on cloning, of course. Late last year scientists at a privately funded lab in Massachusetts successfully demonstrated early stages of growing stem cells in a petri dish by manipulating a human ovum. Several research labs are attempting as well to grow human embryos for the sake of harvesting stem cells. Rather than relying on embryos from fertilization clinics, this research aims to create embryos using DNA from the patient's own cells. Scientists hope that a cloned stem cell would minimize the risk of rejection by the host's immune system.

Is using spare embryos that were created with the intention of trying to have a child morally distinct from creating embryos with the intention of extracting their stem cells? Not to tip my hat to cloning, but I'm of two minds on the matter.

David Batstone, a founding editor of Business 2.0 magazine, is executive editor of Sojourners.