October 6, 2011
Is it Real Progress to Personalized Stem Cells?
A reported advance from the New York Stem Cell Foundation in deriving stem cells from cloned embryos is attracting much attention. Here’s the research paper. The researchers were able to transfer a nucleus from a donor cell into an oocyte which retained its nucleus, and get the oocyte to develop into blastocyst level (70-100 cells), from which they extracted stem cells, which would now be embryonic stem cells (ESC). What’s notable is that this technique of somatic cell transfer leading to stem cell development and harvest had not worked to date with human eggs. That explains much of the attention that this report is generating. However, the catch here is that the researchers found it necessary to maintain the oocyte nucleus while adding in the new nucleus – so the stem cells have extra chromosomes (3 times normal), and are abnormal. It's important to note that the ability to transfer a new nucleus to an existing egg and cause embryo development is the precursor to the long-sought ability to create personalized stem cells. But this report does not put us there. Many of the mainstream news reports oversell the scientific impact here, both reporting it as an unfortunate advance toward the possibility of human cloning, and a fortunate advance toward producing customized stem cells. Both alarm and hope are triggered, out of proportion to the actual results. It’s worth, noting, however, because the public sense of how science is proceeding can translate into demands for oversight or access; thus demands for legislative attention (see, e.g., 1997 Dolly sheep cloning-inspired legislative flurry, see here for an updated list of state cloning laws, and note the origin of such efforts in 1997, when the cloned sheep was revealed). No federal legislation has been enacted, although President Clinton did issue an executive memorandum at the time banning the use of federal research funds for human cloning; in addition, the FDA maintains its authority to regulate any such attempts.
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