I am about tired of hearing how therapeutic cloning, sometimes known as somatic cell nuclear transfer (SCNT) which would create a cloned embryo then destory it for its stem cells, is the "best" or even "only" hope to curing disease. To say this is hyperbole is an understatement. And yet it keeps getting repeated over and over and over again as if saying it will somehow make it so. This editorial is no different. Beside a terribly inaccurate description of SCNT, the editors of the Joplin Globe are guilty of this gross overstatement:
"But for thousands of Missourians today and in the years ahead, somatic cell nuclear transfer is about the only glimmer of hope they have."
I have to ask the Joplin Globe how can some procedure that to date has never worked in humans be anyone's "only" or even best hope? Ethics aside, shouldn't we be a tad skeptical and see if anyone can actually clone a human embryo and extract stem cells from it before we decide it is the "only" hope? I am honestly asking "What hope?"
Let me put this in perspective for you. Researchers ultimately want "pluripotent" stem cells that are a genetic match to a patient and that is why they are pushing for therapeutic cloning or SCNT. But SCNT isn't the only option. In my estimation, there are two ways to get embryonic (or pluripotent) stem cells that are a genetic match to a paticular patient:
You could use SCNT and take the patient's DNA and insert it into an egg and create a cloned embryo. This cloned embryo would be allowed to develop to the blastocyst stage at which point it would be broken open for the embryonic stem cells inside. This is the therapeutic cloning route.
You could take a body cells from the patient and using certain growth media, reprogram them back to an embryonic state. This is the "nuclear reprogramming" route which I have written about in more detail
here.
Ethically, option 1 is a disaster. SCNT would create a cloned human embryo and then mandate that it be destroyed and it is a very real step toward cloned infants. Option 2, depending on how the reprogramming is done, is an very ethical alternative to option 1 because no human organism is created or destroyed.
Ethics aside, which option offers more hope? Beside the fact that no one has actually successfully completed option 1, Ian Wilmut, the scientist famous for cloning Dolly the sheep, votes for option 2, nuclear reprogramming:
But even as Wilmut seeks to get to the starting line in a global race to clone a human embryo, he acknowledged Tuesday that the cloning efforts may be eclipsed. Other scientists, he said, may find a way to create personal lines of healing stem cells without cloning at all.
Joining the cloning experts in the race are scientists who are looking for new ways to "reprogram" DNA, or make it young again without fusing it into an egg. They think it may be possible, for example, to bathe adult cells in the right chemicals and produce stem cells.
"In my view, it is difficult to predict which will come first but I think we need to try both," Wilmut said Tuesday. "If I had to bet money, I would probably bet on reprogramming" rather than cloning.
The science of reprogramming, he said, is moving quickly, and scientists working in the field don't have to deal with the myriad obstacles facing cloning.
So let us break down the obstacles facing both techniques:
In therapeutic cloning, scientists still have to successfully clone a human embryo and extract stem cells. To do this they have to overcome the huge shortage of human eggs needed for SCNT without exploiting young poor women. If they can create a cloned human embryo, scientist then have to get the resulting cloned embryonic stem cells to differentiate into the desired cell type without causing tumors, which to date has been a major hurdle. Even if they get all that working they may have to deal with the potential for rejection from the mitochondrial DNA leftover from the donor of the egg used in the cloning process. (And they have the added hassle of making sure no one implants any cloned embryo to create cloned babies.)
In nuclear reprogramming, scientists have to figure out how to get the right genes turned on to get an adult cell to behave like an embryonic stem cell and they have to get the resulting "embryonic" stem cells to differentiate into the desired cell type without causing tumors.
Considering the numerous hurdles that therapeutic cloning has to overcome to become a viable treatrment option and that researchers are already having success with nuclear reprogramming, I am wondering where the Joplin Globe gets the idea that therapeutic cloning is the "only" hope for some patients.
Frankly, I am sometimes out of hope that the media will get educated and stop beating the cloning drum long enough to see the more realistic hope in ethical technologies like nuclear reprogramming.
Hat Tip: Wesley J. Smith
