Defining Embryo Death
A research team from Columbia University has identified criteria for determining whether an embryo has died. I was aware this work was being pursued. When I was presenting at a stem cell symposium in Rome last year, Drs. Donald Landry and Howard Zucker discussed this issue, and I was impressed with their thoughtfulness and earnest desire to find a way out of the moral impasse in which we find ourselves over ESCR. Here's the idea: If an embryo has died, then taking its stem cells would be no different than, say, removing organs or corneas from a corpse. Since no human life will have been destroyed, there would be no ethical problem. Thus, identifying the "dead" embryos for use in embryonic stem cell research could be a way for both sides of the great debate to achieve their goals and objectives.
The problem is: It ain't about embryonic stem cells from leftover IVF embryos, anymore. It is about human cloning, which is not a synonym for stem cell research--although many biotech propagandists and their willing allies in the media pretend that it is. Moreover, the stem cell/cloning debate is about much more than the sum of its parts. At its core, it is a struggle to determine which value system will control the public policy of society.
So, I applaud the Columbia professors for working on the problem in good faith. Unfortunately, the controversy is much bigger than the relatively narrow issue they are seeking to resolve.
posted by Wesley J. Smith @ 7:07 PM
1 Comments
1 Comments:
Wesley, I can understand the breadth of the issues you're referring to. I suspect that as the black box of death criteria is opened we'll figure out that there has not been sufficient philosophical 'due diligence' on a variety of basic issues.
In my own experience of working with early-stage zebrafish (Danio rerio) embryos in research, I have attempted to identify criteria for the sensation of pain and discomfort as well as for death. Because of the relatively rapid development that takes place in zebrafish compared to humans, it was possible to observe over a short period of time what could be thought of as analogous to a wide range of developmental stages in human embryos.
I found it quite difficult to establish viability criteria outright and was forced to rely on a series of measures such as the presence of pulsatile tissue in the thorax, spontaneous movement, and/or responsiveness to stimuli (mainly touch). However, these criteria were useful only for more advanced developmental stages. Among the earliest-stage embryos, I did notice the relevance of something like the hypocellularity and lack of compaction criteria.
This recent article would've been helpful to me at the time, but it also would've raised ethical questions that seem to pass under the radar of the majority of regulatory bodies. At our institution, there seemed to be little if any regulation of the use of early-stage zebrafish embryos because these criteria had not been established and because the questions of value and sentience had been dealt with on a more pragmatic level. The general rule of thumb for zebrafish research is that regulatory oversight is necessary when the animals approach the stage of development at which they begin to feed independently. The number of days post-fertilization at that point may be analogous to third-trimester human development or later. That suggests that the viability criteria we apply to at least this particular non-human species may be limited by our ability to delineate the relative value of life of humans as opposed to this species.
Even given certain criteria, there is the possibility that we may be incorrect. For example, during my experiments there were many embryos that exhibited no viability criteria on a given day that on subsequent days were obviously viable according to the same criteria. I think this may have been true of even the early-stage embryos, for which the hypocellularity and compaction criteria would've been relevant. Some embryos passed the tests of viability but were obviously anomalous in their development.
Even the neurological criteria for the death of developed humans are the results of developments beyond previous criteria. Despite our 'advanced' criteria, we can't escape the essential questions of value of life and the meanings of life, death, and pain and discomfort.
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