Quotes of the Day

With an investigative panel from Seoul National University (SNU) scheduled to deliver its final report this week on Dr. Hwang Woo Suk's already largely discredited stem-cell research, the South Korean scientist's career seems all but finished.

Why did Hwang's claims create such excitement?
In a 2004 paper, Hwang reported that his team was the first to clone human embryos and extract lines of embryonic stem cells (ESCs) from them, harvesting a single line of ESCs from experiments involving 248 human eggs. ESCs can potentially grow into any type of body tissue, and lines created through cloning might one day help treat conditions like Alzheimer's or diabetes without the risk of immune rejection. In 2005, Hwang claimed to improve his process, using an average of 17 eggs to create an ESC line.

So what went wrong?
SNU says that Hwang used far more eggs than he had admitted. Egg donation carries a small risk of serious side effects. Hwang's technique would likely never become a viable treatment if each ESC line required hundreds of eggs to produce.

So where does that leave the field of ESC research?
Not as badly hurt as it may seem. "There are 20 years of research, and one set of lies won't trash the whole field," says Christopher Thomas Scott, Stanford University bioethicist and author of the book Stem Cell Now. The bigger backlash is likely to be political, as the scandal gives further ammunition to those who view ESC research as inherently unethical. Still, other methods of ESC research will continue to develop across the world.

• By Bryan Walsh
• How Much Damage Was Done?