This is why it was such a risk for California to earmark $3 billion specifically for stem cell research over the next 10 years. Stem cells are just one of many promising fields of biomedical research. They could yield great advances, or become an exercise in sustained failure, as gene therapy has so far been. By allocating so much money to a single field, California is placing an enormous bet on a single horse, and the chances are substantial that its taxpayers will lose their collective shirt.
Stem cell researchers have created an illusion of progress by claiming regular advances in the 12 years since human embryonic stem cells were first developed. But a notable fraction of these claims have turned out to be wrong or fraudulent, and many others have amounted to yet another new way of getting to square one by finding better methods of deriving human embryonic stem cells.
The major advances in stem cell biology have come from molecular biologists who study transcription factors, the master control switches that govern the cell's operations. The Japanese biologist Shinya Yamanaka showed that with a mere four of these factors, which he cleverly guessed, he could force an ordinary cell to walk back to embryonic state.
But the finding illustrates what stem cell research is really about. It's not about therapies and quick cures, it's about understanding the basic nature of human cells and what makes one type different from another even though all have the identical genome. In other words, it's a basic research program with little likelihood of producing therapeutic gains in the near future. Stem cell scientists, while generally avoiding rash promises themselves, have allowed politicians to portray stem cells as a likely cure for all the major diseases.