Here we go again. The Boston Globe reports:
Scientists at a little-known California biotechnology company today claimed to have cloned a human embryo theoretically capable of yielding stem cells, but fell short of generating the avidly sought blank slate cells through the process.
The work by Stemagen Corp. won only faint praise from top figures in the field, who said that though the claim appears supported by the research, this simply provides more evidence that humans can be cloned, like sheep or mice. At least one European laboratory has already cloned human embryos, although to a less advanced state, using a different process, and with less scientific certainty than that described by the La Jolla-based company in the somewhat obscure journal Stem Cells.
The lead scientist at Stemagen, however, called the work an advance toward the goal of creating new lines of "true" embryonic stem cells using a process know as somatic cell nuclear transfer, or therapeutic cloning.
"No other scientific group has documented the cloning of an adult human cell, much less been able to grow it to blastocyst stage," said Andrew J. French, Stemagen's chief scientific officer and lead author of the research.
A blastocyst is an embryo about five days old and containing 50 to 200 cells. This is the stage at which stem cells—capable of forming any of the body's 220 cell types, including blood, bone, or nerve tissue—can be culled for research or therapy, a process that destroys the embryo.
The research drew criticism from religious groups opposed on moral grounds to using embryos for scientific research.
Leading stem cell scientists not involved in the work described Stemagen's research as seemingly solid, but not especially useful since it failed to forge stem cells.
University of Pennsylvania bioethicist Arthur Caplan notes:
Why do scientists need to clone embryos to get stem cells? Didn't we spend the last days of 2007 rejoicing that scientists had found ways to create stem cells using methods that do not rely on embryo destruction of any kind?With the appearance of some new scientific tricks to get adult cells to act more embryo-like, scientists, the president and a host of pundits declared the end of the long stem cell research battle. Not so fast. Not everyone thinks reprogramming adult cells to make them act like embryos is going to work. If you want to build your own repair kit to fix damaged heart muscle, torn nerves, severed spinal cords or worn-out joints, then cloning from your own healthy cells still strikes many as the way to go.The California company is among those who see human cloning as the best source of stem cell repair kits. It's too soon to tell if they are right.
The stem cell wars may be about to heat up again. Watch for presidential hopefuls to weigh in on this issue.