Stemagen, a private company in La Jolla, Calif., has published a paper in which its scientists claim they have successfully created cloned human embryos. If you think you have heard this announcement before, you are right.
Just about two years ago, a team of scientists at Seoul National University in Korea announced in the journal Science that they had cloned human embryos and had gotten stem cells to grow from them. The Korean work could not be replicated. Eventually Hwang woo-suk, the lead scientist involved, admitted he had lied. There were no cloned embryos. He resigned his university position in complete disgrace.
So, two questions arise about today’s human cloning news. Did Stemagen scientists really do what they are saying they did? If they did, what does it mean for the future of human cloning and stem cell research?
The only way to prove that Stemagen team has succeeded in making a human embryo — 10 years after the cloning of Dolly — is for someone else to replicate what they did. That will take some time.
The California group was very cautious in presenting the evidence in its just-released paper. Scientists checked the DNA carefully in the donor cells from which DNA was taken and in the embryos which were cloned from that DNA to make sure it was the same. And they had an independent laboratory confirm the result.
There are enough checks and balances reported in the paper — and a keen awareness by the authors of the fraud perpetrated by the South Korean group — to believe that they are really the first to achieve the cloning of human embryos in a verified, peer-reviewed process.
Now that this is done, what does it mean?
No interest in human clones
Some will argue that the creation of human cloned embryos brings us that much closer to the cloning of adult human beings. Now, the prospect of human cloning has become more real.
Nonetheless, no one at the company has any interest in making human clones. Hollywood loves the prospect of human cloning. Science does not.
For Hollywood, human cloning offers great story lines and plenty of freakiness for audiences who aren’t quite sure what to expect when a clone moves into their neighborhood. Forget the fact that if there were human clones, they would pose no special threats to anyone. Nasty, vicious human clones are better for TV ratings and box office receipts.
Scientists don’t care about human cloning. They know the fame and the monetary rewards lie in turning cloned human embryos into stem cells that can be used to repair damaged tissues and body parts. When it comes to human cloning, the future will involve manipulating eight-cell embryos to repair damaged brain cells for people with Parkinson's — not deciding what to do about the evil clone army threatening the Northeast corridor.
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.
Where to get the eggs?
There is, however, a huge boulder in the path of companies like Stemagen who are betting on cloning to get them to the holy grail of stem cells that can be turned into curative cells. Where to get the eggs needed to make human embryonic clones?
In the paper announcing the breakthrough, the authors note that they got three out of 25 attempts at clones to turn into human clone embryos. That is a success rate of about 10 percent. Even if that success rate improves in the future, it still means that six or more eggs are going to be required for a researcher to make a stem cell from a clone made from the DNA of one of your own cells.
Where will hundreds of thousands of eggs come from when hundreds of thousands seek cures? Will we pay poor women to create them? Egg-farming, using powerful drugs with serious risks, may not be the most humane way to ask a poor woman to earn a living.
The cloning of human embryos has now been accomplished. 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.