Human embryonic stem cells (hESC), new cells that are basically a biological blank slate, become more specialized as they develop and contribute to a number of organs and tissues. As such, they have the potential to treat diseases such as Parkinson’s but their progress has been slowed because of the ongoing ethical debate over how human embryonic stem cells are derived.
Some European countries - Austria, Germany, Ireland, Italy, Norway, Poland, Slovakia and Switzerland - forbid the creation of new hESC lines surplus embryos, even ones that remain from infertility procedures. In June, 2006 the EU parliament only narrowly agreed to fund stem-cell research, and then only as long as it excluded activities that involve destroying human embryos. In the US the restrictions are similar.