Part of the show Obesity, Appetite, Exercise and Weight Loss
Although science is often seen as perfect, things can go wrong and the Christmas holidays saw the world rocked by a stem cell scandal. Last year, South Korean scientist Woo Suk Hwang announced that he had managed to clone human embryos and make stem cells out of them. But now other stem cell scientists have used genetic fingerprinting techniques to show that Hwang's work was fake. So the prize of cloning the first stem cells is still up for grabs. But it's not all bad news for stem cells. This week, researchers in the US announced that they had managed to make human embryonic stem cells without the use of any animal products. Normally, stem cells need things like cow proteins in order to grow, but such products carry a risk for sparking allergies, or carrying animal viruses. So this is an important breakthrough as it means we can now make stem cells that are much more suitable for transplanting into patients.