Everything you always wanted to know about the stem cell debate

George Bush's opposition to stem cell research is intellectually and morally incoherent. Here's why.

By Farhad Manjoo

Jun 8, 2005 | Once again, George W. Bush finds himself confronting a nettlesome ethical and political debate that has intermittently dogged his presidency -- the fight over the future of embryonic stem cell research in America. Late last month, over the White House's strong objections, the House passed legislation to increase federal funding for the research, and the Senate looks certain to do the same in coming weeks. Religious conservatives vigorously oppose the stem cell bill and Bush has promised to veto it if it reaches his desk.

What's remarkable about Bush's stance is that just about every survey taken on the issue shows that all but the most ardent right-wingers support expanded funding for embryonic stem cell science. Yet Bush seems to have paid no political price for his restrictive policy. When he first dealt with the issue during his first year in office, he came up with a stem cell plan that pleased neither scientists nor moralists -- but it was quickly forgotten after 9/11. Stem cells again made a brief appearance in last year's campaign, when Ron Reagan, among many other Democrats, tried to drum up support for research at the Democratic National Convention. Obviously, the pleas didn't hurt Bush very much. Americans may have opposed his policy, but clearly stem cells weren't a deciding factor for many voters in November.

It's possible that Bush will once again dodge the stem cell bullet. He could veto this bill, keep the GOP rank and file from pursuing an embarrassing congressional override, and put the issue behind him, never to hurt him or his party's political fortunes again. If so, it may be thanks to publicity stunts like the one he staged the day the House passed the stem cell bill. Bush invited to the White House two dozen children who had been born from frozen embryos. He suggested that lawmakers who defy him on stem cells were actually working against these children's interests.

Now, those babies were adorable. And a cute baby goes a long way in defending a nearly indefensible public policy position, especially when the debate is as complex as the one surrounding stem cells.

Here, then, we present our guide to help you see through the fog created by Bush's publicity ploys: a thorough explainer on stem cell research, and the facts you'll need to follow the upcoming debate. To assemble this FAQ, we spoke to scientists, ethicists and political activists on both sides of the stem cell fight. We can't promise our efforts will lead to a more enlightened stem cell policy -- but perhaps, at least, we may have a debate on the science that's unimpeded by cheap publicity stunts.

Let's start with the current debate. What is the bill all about?

The Stem Cell Research Enhancement Act of 2005 (read the text here) would increase federal funding for scientific research on embryonic stem cells. Specifically, the bill would let the government pay for research on stem cell lines derived from embryos stored at in-vitro fertility clinics. Currently, under a policy put forward by President Bush, the government will only fund research on a very limited number of stem cell lines.

Wait, hold on. You're already losing me. "Stem cell lines"? Can you start with a short primer on stem cells? What are they?

Stem cells are what scientists describe as "undifferentiated" cells, meaning they have not yet specialized to perform specific functions in the body (like, for instance, acting as part of muscle tissue or blood or the nervous system.) They are found in the human body at any age -- in embryos, in fetuses, and in adults -- where they act as the root (or "stem") of all the cells that make up our tissues. In other words, all of our cells arise from stem cells.

OK. So why are scientists interested in them?

Such cells exhibit two important, unique properties. First, you can think of stem cells as immortal. When stem cells are removed from the body and studied in a lab, they can be made to indefinitely self-replicate, creating a pool of exact copies of themselves. One of these pools is called a "stem cell line" -- a practically limitless factory of stem cells.

Stem cells are also uniquely flexible; you can think of them as being essentially "programmable." Under the right conditions, scientists can coax a stem cell into becoming a specialized cell, a blood cell, a liver cell, a brain cell.

And how does that help us?

Well, taken together, these two features, self-replication and flexibility, make stem cells remarkable, almost magical things. Some scientists imagine stem cell lines someday serving as cellular "repair kits" for the body. If researchers can perfect the techniques to grow and direct stem cells into becoming specific kinds of body cells -- currently a very big, contentious "if" -- they foresee a future in which new, healthy cells can be created in a lab, and injected to replace diseased cells in the body. Stem cell therapy, scientists hope, may treat or cure a host of ailments beyond the reach of medicine today, including, to quote from the Web site of the International Society for Stem Cell Research, "Alzheimer's disease, cancer, Parkinson's disease, type-1 diabetes, spinal cord injury, stroke, burns, heart disease, osteoarthritis and rheumatoid arthritis."

Next Page: Tom DeLay: Stem cell research is "exploration into the potential benefits of killing human beings"

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