April 22, 2024

Human embryos cloned, but scientists “underwhelmed”

The clincher, producing a stem cell line, is yet to come

After a decade of trying and a
spectacular fraud in South Korea, a California company has cautiously
claimed that it has cloned human embryos. In a paper in the journal
Stem Cells, little-known Stemagen says that it succeeded in fusing an
adult skin cell with an egg. Its scientists managed to grow five
embryos to the blastocyst stage from 25 eggs, suggesting that the
technique is relatively efficient. However, they did not create stem
cell lines, which sceptical rivals say is the touchstone of true

Stemagen’s CEO, Dr Samuel Wood,
called his team’s achievement “a critical milestone in
the development of patient-specific embryonic stem cells for human
therapeutic use”, including Parkinson’s and Alzheimer’s.
The chief scientific office at a rival company, Advanced Cell
Technology, sniffed that Stemagen’s work was "underwhelming"
and that its embryos "look very unhealthy, at best".

As this milestone has been so long
anticipated, bioethical comment on Stemagen’s work raised two
evergreen issues. If it works, where will the eggs come from? Won’t
this lead to mass-producing human embryos in order to destroy them?
But now, after the discovery by a Japanese team that it is possible
to reprogram ordinary skin cells into pluripotent cells, there is a
new question. Why bother with ethically-fraught cloning if these new
cells can do the same job?

The answer is that scientists need to
keep their options open, answers prominent bioethicist Arthur Caplan.
“Is it a viable strategy for creating stem cells to cure
diseases? A lot more research will have to be done to find out. While
we wait, let’s not be frightened by scare tactics into not
funding research that may be the key to curing what is currently
incurable”. ~ Stemagen; MSNBC.com, Jan 17; Boston Globe, Jan 17