Alan Trounson, PhD, president of the California Institute for Regenerative Medicine, co-authored a comment piece published yesterday in Nature discussing the issues surrounding therapeutic human cloning. The comments were sparked by last month's announcement by researchers at Oregon Health and Science University of the successful derivation of embryonic stem cells from cloned human embryos. Although problems with the original research article have since surfaced, the crux of the finding remains unchanged. The article explains:
This formidable technical feat is potentially a key step towards developing replacement tissues to treat disease. Media coverage of the paper has also rekindled long-standing controversies about human cloning, the use of human eggs and the destruction of human embryos. The achievement is a timely reminder that scientists must remain actively engaged in discussions about the ethics of using human embryos for research in cell biology and regenerative medicine.
The researchers used a technique called somatic cell nuclear transfer, or SCNT, to create the embryonic stem cells. In SCNT, the nucleus of a mature, donated human egg is replaced with the nucleus from a cell from another individual. The egg is then stimulated to divide and become an embryo carrying the genetic information from the donor nucleus. The process would conceivably allow researchers or clinicians to create unique embryonic stem cell lines to match individual patients and would avoid issues of immune rejection that could arise with non-genetically matched ES cells. But it's also the first step in potentially cloning a human for reproductive purposes.
In the article, Trounson and his co-author, Martin Pera, PhD, from the University of Melbourne, urge caution and proactive consensus building to address the many complex ethical and biological issues surrounding this type of work. It's a very interesting read. They conclude:
The potential benefits of stem-cell research are immense. Prospects for transformative treatments for conditions such as macular degeneration, type 1 diabetes or Parkinson's disease are now on the horizon. But without first convincing governments, the public, and funding and regulatory bodies that all the possibilities have been thought through and evaluated, headline-catching results could create a backlash that unnecessarily delays the tremendous potential benefits of cell therapies.