Hope, because they promise to cure a breathtaking variety of conditions, ranging from Parkison’s disease to the damage caused by heart attacks. Stem cells may one day even be used to grow entirely new limbs and organs.
Controversy, because the most potent form of stem cells, those derived from human fetuses, are just that – derived from human fetuses. Proponents of embryonic stem cell research argue that the source is not human, while those opposed say such research is morally wrong.
What you should know, however, is that stem cell research goes far beyond embryonic research. So even if you oppose it, it almost goes without saying that general stem cell research is a very good thing.
First, everyone has lots of stem cells – they’re responsible for a great deal of the natural cell cycle in your body. Stem cells are simply cells that aren’t committed, so to speak.
Think of it like this: when you’re a kid, you could become a professional dancer, mathematician or even President. When you’re 50 years old, however, you are something and can do a lot more than when you were a kid. On the other hand, you have a lot less potential than you used to.
Most of your body consists of very specific tissue, like blood cells and say your immune system T lymphocytes. Those are “grown up” cells, and the sad fact is that many of them lost genetic material and potential in becoming so: Red blood cells don’t have DNA altogether, while T cells have lost significant chunks of their DNA. Waiting to replace those differentiated cells are stem cells.
Stem cells, on the other hand, have more potential and are responsible for replacing and generating most cells in the body. Every day, in your bone marrow alone, they generate over 370 billion immune system cells. Your skin is constantly regrowing.
If differentiated cells are like adults, then the stem cells you have are like a 20 year old you. Capable of a lot, but not everything. You’ll never become an Olympic level skater if you start at that age, for instance.
What this means for your body is as follows: while your stem cells can create and regenerate blood cells, they can’t replace brain or heart cells. If you get cut, you can recover fully (well, almost fully. The tissue damage is in some ways permanent). But if you have a heart attack, your heart will never be as good as it was before.
Unfortunately, however, what we have can’t do everything. If you suffer a heart attack, none of your stem cells will fully repair the damage. The same is true for damage to your brain, such as might be caused by a concussion or stroke.
The savvy reader might ask the following: then where did the brain and heart come from? The answer is relatively simple and explains a lot: When we were a fetus, the stem cells we had were even less differentiated or specific than the ones we currently have. They were indeed capable of turning into anything.
Embryonic stem cells can turn into any tissue whatsoever, which is why they hold such potential for researchers.
The use of fetuses for medical research is not an easy subject and raises very difficult questions. We all agree that there is nothing wrong with wasting living material that just has the potential for human life. Masturbation and menstruation, while certainly not dinner topics (at least in my house), fail to evoke moral outrage.
Does sperm fertilizing an egg instantly convey humanity? My personal opinion is no. But at the same time, I feel icked out by the idea of harvesting fetuses for scientific research. This conflict, for me at least, is made easier by the fact that many of the fetuses used for research are already discarded as a by product of in vitro fertilization.
As you can imagine, however, stem cell research goes far beyond the embryo. It is entirely possible that the stem cells we as adults have can be trained in a lab to turn into all sorts of tissue.
Some of the most exciting research going on today, and which I was a small part of, is based on the following idea: Why can’t we turn a regular cell into a stem cell, as most cells do have all of their DNA? Doing so could create artificial stem cells that are as powerful as those from a fetus, and would totally circumvent most of the moral issues.
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David Gurevich writes about health and medical issues at HealthLifeandStuff.com. He is an undergraduate at an Ivy League School where he has studied biology for several years and has been published on stem cells. He invites folks to join his AIDS Awareness Initiative where $750 in cash prizes will be given to blogger participants.