Stem cells are cells in an early embryo which are able to develop into any type of cell in the body.
Recent US research shows that they can be isolated, kept for long periods in the laboratory, and then chemically induced to become almost any chosen type of cell. The hope is to make replacement body cells which could be injected into patients to treat a range of degenerative diseases like Parkinson's, diabetes and heart failure. That goal is still very far off. It also poses a major ethical problem. For many Christians, the present Act had stepped over an unacceptable boundary.