Like everyone else in science, I have deep respect for the Nobel Prize. Yet I most often refer to this summit of recognition for scientific achievement to humble rather than praise it, in the context of what matters most. Lifestyle — eating well, being active, not smoking — can slash the risk of almost all chronic disease and premature death by some 80 percent and change the behavior of our very genes, and will never earn anyone a Noble Prize. But no Nobel Prize ever conferred was for an advance that offered even a fraction of such comprehensive promise.
Yet while I routinely advocate for greater attention to the use of what we already know rather than devoting quite so high a percentage of our capital — human and financial — to the pursuit of what we don’t in order to advance the human condition, I make an exception for stem cell research.
Stem cell research is highly technical, and I am by no means expert in its intricacies. But that expertise is not necessary to understand the basic principles, and the stunning potential.
When sperm meets egg, first one, then two, then four, then eight cells develop. These are embryonic stem cells, also referred to — perhaps misguidedly, as it evokes the mistaken image of a tiny, full-formed person — as an embryo.
To casual microscopic inspection, these eight cells look absolutely identical. In fact, these cells are truly identical in every way but one, and that one only matters to the cluster of cells rather than any one of them.
Mixed in with all the rest of our DNA is a family of Hox genes. These genes are a sort of cellular compass, and establish directionality — as in, I am in the cell to the left, you are in the cell to the right, you are near what will be feet and I am near what will be head. This tiny, isolated bit of differentiation sets in motion the differential development of body parts that reliably sets our heads atop our necks, and our feet below our ankles.
But other than in the inscrutable orientation of their Hox genes, embryonic stem cells are the same in a profoundly important way: They can turn into anything from lip to liver, heart to humerus. They are, in scientific terms, “totipotent” — they have the potential to be anything.
That is the reason why, despite the resistance to human embryonic stem cell research from certain quarters, scientists have argued passionately that there really is no substitute. Other types of stem cells are “pluripotent” — they can turn into a range of tissues, but the “totipotency” of embryonic stem cells stands alone.
So, too, does the medical promise of stem cell research. Many degenerative and autoimmune diseases involve the destruction or dysfunction of a key family of cells: type 1 diabetes, multiple sclerosis, Parkinson’s disease, Alzheimer’s and many more. The ultimate solution to these conditions is to replace damaged cells with healthy ones.
The same is true when cells are destroyed by trauma, as in spinal cord injury. Stem cells can, potentially, fix all of these conditions. But first, we need to understand and control them.
For that to occur, research is required. So it is that I, along with innumerable scientists and even more innumerable patients, celebrate the news that federally funded stem cell research is viable once again, with 13 approved stem cell lines and more to follow.
It won’t surprise you that as a left-leaning public health professional, I have supported stem cell research all along. It might surprise you a little to learn that I have also respected the views of those who do not. If your perception is that “life” starts at conception, there is simply no way to lend your support to stem cell research.
The new policy permits federally funded research with “ethical” stem cell lines only. In essence, this means surplus embryonic cells produced during in vitro fertilization efforts, and destined for destruction if not research. If there is still an ethical dilemma, it is no longer about stem cell research — it is about in vitro fertilization. Anyone opposing the generation and destruction of surplus embryonic cells has an argument with the clinics that help desperate couples bypass biological limitations and start a family. I think one could argue against this, but few people do. Once we allow this practice into our prevailing societal ethic, then allowing for constructive use rather than pointless destruction of “surplus inventory” isn’t asking for much. So we either sanction in vitro fertilization, or we don’t. And if we do, constructive use of stem cells imposes no additional harms of any kind, and a whole new world of potential benefits.
I hope my organs are put to good use if I die prematurely- and I bet most of you feel the same way. If a fully formed, conscious human being would prefer a meaningful to a meaningless demise, I see little down side to extending this same consideration to a far-from-fully-formed, far-from-conscious cluster of identical cells.
Arguably, a compromise is an agreement that satisfies no one. The stem cell solution could be viewed that way. Dedicated advocates of stem cell research would like fewer restrictions, and opponents are doubtless unhappy that this research is happening at all.
But as for me, I find it encouraging that the current policy demonstrates respect for both points of view. I see promise in that approach to policy, just as I appreciate the promise of stem cell research itself.
Maybe the current solution isn’t perfect. But I think the cup of stem cells available for research is now half full.
By Dr. David L. Katz
Dr. David L. Katz can be reached at www.davidkatzmd.com.
