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Stem cells: It’s all about life

Rights of embryos | Cell lines and other scientific issues | Are stem cells really that good? | Prop. 71.

[Written October 20th, 2004. The proposition passed, despite deficiencies in funding oversight, public ownership of eventual patents, and conformity to California's sunshine laws. The industry, unfortunately but not unexpectedly, has jumped on these loopholes. Whether this ruins the whole initiative remains to be seen.] [Comment added approximately December 2004.]

Stem cells have become the umpteenth topic in the culture wars. The Bush-Cheney ’04 campaign made it something of an issue (although maybe they acted in haste and are now repenting at leisure, since it loses them more votes than it gains), and we Californians have a high-profile Proposition 71 on the ballot to kickstart research despite the lack of federal funds. Lives were always involved, but now money is part of the picture and the discussion has heated up.

What about the rights of embryos?

Part of the complexity is that a whole series of interdependent questions must be answered to come to an informed decision. They start with the big one of which lives are more important, embryos’ or patients’? That’s the way the question is usually framed.

And that’s why it is unanswerable.

The real first question is whether the early-stage embryos providing the stem cells are human beings. If they are, they can’t be used to save other lives, and that’s all there is to it. If they aren’t, there’s nothing left but a few technical issues and a lot of shouting about how much money to spend.

So, beginning at the beginning, consider the facts regarding human embryos. Biologically, early-stage embryos have less nervous system than a clam. Clams are sentient, but it’s hard to say a lot more for them. It has to be agreed that embryos don’t have a human mind, but at least they do have human DNA. However, every scraped knee leaves behind countless cells packed with human DNA, yet we don’t have funerals for them. Nor do we feel that a transplant recipient has turned into two people after the operation. Having human DNA is not enough.

The final refuge is to say that an embryo *could* become a human being, even if it isn’t yet. But potential humanity is not enough either. Given modern in vitro fertilization techniques, every human egg in the world could be fertilized and turn into a human being. Nobody regrets all the wasted lives because, really, they aren’t. Potential is not the same as actual, any more than my potential to win a Macarthur grant is equivalent to winning one.

The fact is that embryos are not recognizably human by any objective standard. We’re really arguing about something much harder to define. We’re trying to decide whether embryos have the essence of humanity. Call it a soul, for short.

Putting it in plain terms shows that we’re really arguing about a *belief*. Arguments about beliefs cannot be settled, and that’s why the argument about patients’ versus embryos’ rights keeps going around and around and around. That argument is pointless, and our personal beliefs about the embryo’s human status are relevant only to our personal behavior. What matters is that beliefs can legitimately conflict in a matter where the facts are unclear, and public policy has to be separate from the beliefs of any one group. In other words, beliefs and state must be separate. It’s the only way.

Nobody can prove that an embryo is or is not a full human being, so those who believe embryos are not yet human should be free to act accordingly, and those who believe they are human, likewise. Stem cell therapy shouldn’t be forced on anyone, but neither can anyone demand that it be banned.

A side issue is whether people can legitimately be asked to fund actions they oppose. For the large ethical questions involving life and death, the answer seems to me to be no. However, pacifists are taxed to fund wars. People who consider it state-sponsored murder are taxed to fund capital punishment. One group should not be given special consideration in taxation. Either all conscientious objectors should be free to withhold funds, or none should.

Research on stem cells is a legitimate endeavor, so lesser questions are not just a waste of time. Let’s go to it.

Stem cells, schmem cells. What are the scientists talking about?

First, why not use adult stem cells? Because, for the most part, we can’t yet reliably find them, grow them, or use them. Medical use of these cells is many more years in the future than is that of embryonic ones.

Another issue is that early-stage embryos don’t have much of an immune system. This means that there may be no rejection issues with embryonic stem cells. And that means those cells can be given to any patient who needs them, without having to tailor each therapy to a specific person. Given social realities, adult stem cell therapy would be so expensive and labor-intensive that, at least for the first few decades or generations when it was available, only the rich or well-insured would benefit.

Umbilical cord cells are harvested at birth, when the newborn has a well-developed immune system. (The umbilicus is genetically part of the fetus, not the mother.) Thus, without lifelong anti-rejection drugs, they will only be usable by that individual, the same as adult stem stem cells.

Second, what is “somatic nuclear cell transfer”? One side says it involves destroying embryos, the other says it doesn’t. Well, they are both right, in a way. The technique, like use of adult stem cells, is a therapy usable only by the person involved (without anti-rejection drugs). The patient provides a cell nucleus, which contains one copy of that person’s DNA, all 46 chromosomes. This is injected into an egg cell whose own nucleus has been removed. The non-nuclear part of the egg is what starts cell division, so the resultant egg+nucleus starts dividing and creates a small mass of cells which can be used as stem cells. In humans, there have been no documented cases of successfully getting these cells to organize into a healthy embryo that can develop to term. Human embryonic development turns out to be more complex than that of mice and sheep, so cloning Dolly is not the same as cloning people. Even when human cloning is eventually successful, use of this method is only objectionable if you believe embryos are human. That goes right back to the whole essentially philosophical argument about the status of embryos.

Third, why not use the existing cell lines? The federal clampdown on research happened at such an early stage that there are nowhere near enough different embryonic lines for medical use. In a very loose analogy, it’s as if kidney transplants were the only ones doctors could study. There’d be no liver, pancreas, heart, or lung transplants.

Even worse, the existing lines were intended for research, not direct medical application. As such, they were grown using mouse feeder cells, and may contain mouse DNA and mouse viruses. Consider that HIV is a virus that crossed species from monkeys to us (most likely while butchering bushmeat), and it becomes obvious why nobody in their right minds would use those cell lines in medicine.

Are stem cells just another big scientific pie-in-the-sky?

The puncturing of the high tech bubble has left many people with the feeling that biotech is all hype. Genetic engineering didn’t make us all tall and thin and blond. It didn’t even give us immortality.

There is a big difference between stem cells and genetic engineering, even if both are done by people in white coats peering into petri dishes.

Genetic engineering involves fiddling with an individual’s actual DNA. DNA is very resistant to fiddling. If it wasn’t, you’d be dead. Viruses are the only natural method of interfering with it, which is why genetic engineers use a form of weakened cold virus to insert the bits of DNA they want into the cells. But that’s not all because the bit has to go into the *right place*. That’s largely a matter of luck. Then, cells die. The new cells are made according to the original (faulty) template, and need to be engineered all over again. This sequence of events describes what happens when everything is working perfectly. Anyone who knew anything about it knew that genetic engineering was being wildly overhyped among non-scientists.

(This is not to say genetic engineering doesn’t hold a lot of hope for the future. It does. It’s our only real chance to cure the common cold, for one. But, as the scientists say, much work remains to be done.)

Stem cells are a different matter. There is no messing with intricate cellular processes. On the contrary, the stem cells do their own thing without assistance. All they need is to be given the conditions for growth, whether that’s in a petri dish or inside a person. The situation is much more analogous to an organ transplant, except that the organ is tiny, and doesn’t even need to have blood vessels hooked up. We know how to transplant organs, and we know how to transplant stem cells. What we don’t know is exactly how to use them (although in some applications, we do know that at this point). The methods to learn how to use them are pretty well worked out by now.

So, yes, stem cells are extraordinarily promising. And yes, there will be many needed applications in the near future. Some recent examples are regrowing heart tissue and regrowing retinal tissue in certain kinds of blindness. Cures for diabetes and Parkinson’s are straight matters of transplanting the necessary cells into the relevant organs. Farther down the road, stem cells will allow improved nerve growth and hence cures for spinal cord injuries. Furthest of all, they’ll eventually allow lost limbs to be regrown. Stem cells are the biggest thing in medicine since the invention of antibiotics. Come back and talk to me in five years, if you don’t believe me now.

Coda for Californians: Are stem cells worth the money?

California is the place currently struggling with this issue because Proposition 71 is on the November 2nd ballot. Prop. 71 gives three billion dollars to fund stem cell research, the idea being that California will reap gigabucks from becoming a biotech mecca. Singapore has already done something similar by throwing two billion dollars at stem cells, which has made it one of the foreign destinations draining away scientific brains who can’t do their work in the US federal climate.

Several questions arise. For instance, if stem cells are so marvelous, why does the taxpayer and our government need to get involved? Why aren’t the venture capitalists funding the research? I think it’s simply because of the vast sums involved. The task is to launch a new industry whose startup costs are on the order of a few billion. Even Bill Gates might hesitate. It’s a project of a magnitude that can really only done by a large, technologically advanced society. California is one of the few entities smaller than a nation that even has a hope in this regard.

One flaw of Prop. 71 is that the state government provides seed money, but there is no provision for a cut of subsequent royalties. If stem cells are going to be lucrative, why isn’t the taxpayer getting a return? Why indeed. Taxpayer-funded development without any subsequent return to the government is an entrenched idea at this point, even though it shouldn’t be. It’s part of the whole ethos of socializing risk while privatizing profit. It would be a good topic for the Legislature to act on, or, failing that, for yet another initiative. But voting down this initiative for that reason alone will do nothing but accelerate the brain drain we’re already suffering to other countries with stem cell-friendly policies.

There are other, less valid, objections to financial provisions of Prop. 71. There is, supposedly, not enough oversight. Fraud must be rigorously and totally guarded against. But to suppose that desk jockeys or committees have a better understanding than scientists of how and where to spend stem cell research money is simply delusional. Federal funding of research has shown how easy it is for bureaucrats to push research into pet projects that go nowhere. We need less of that, not more.

The exceptions to sunshine laws are because of the extreme financial incentives to rip off this type of research. If everyone knows what’s going on, some people are going to take dishonest advantage of it. Things shouldn’t work that way, but it is a reality we have to deal with.

So, to put it in a nutshell, stem cells do hold enormous promise. The payoff is likely to be vast, especially because stem cells will also open whole new ways of making money that didn’t even exist before. The human benefit is incalculable. The earliest applications are very few years, not decades, away. I’m a biologist, and to me the financial arguments against Prop. 71 sound just plain silly.

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