Scientists reeling from the revelation that South Korean researcher Hwang Woo Suk's stem cell work was fraudulent are scrambling to revive the golden promise of the field and make up for lost time. "The sad thing is that thousands of people may die because we lost two years of legitimate research while the South Koreans played their games," says Robert Lanza of Advanced Cell Technology in Worcester, Massachusetts.
Hwang claimed to have perfected somatic cell nuclear transplant, a procedure in which genetic material is removed from a donated egg and replaced with DNA from the patient to create cloned cells that could regenerate diseased tissues or organs. The technique is appealing because the cloned cells would be genetically identical to the patient's own and so should not be rejected. After Hwang's papers were published, Advanced Cell Technology had to suspend its research in the area; funding had dried up, and the company's egg supplier had cut off its shipments, saying that the goal had already been achieved. The project has been restarted, and researchers are exploring new ways to create stem cells.
In one promising approach, cellular reprogramming, stem cells can be generated by fusing adult skin cells with embryonic stem cells from existing cell lines. The catch is that the new cells still contain DNA from the original stem cells, so they don't match the patient's exactly. Another possibility is harvesting cells from an egg that is stimulated to divide as if it were fertilized; the resulting cells, lacking half the usual genes, could be closely matched to a wide variety of recipients. Finally, stem cells from umbilical-cord blood may be medically useful, although they do not have the therapeutic flexibility of embryonic cells. "It's unfortunate," Lanza says. "Here we are, two years later, back at square one."