{description}Every human being begins as a single stem cell. This stem cell has the power of virtually unlimited division and proliferation until it differentiates into a specialized cell, such as a muscle cell. Since human embryonic stem (hES) cells can be cultured to yield different tissues and organs, many scientists believe they hold great promise for regenerative medicine. Diseases such as muscular dystrophy, Parkinson’s disease, heart disease, and vision and hearing loss might be treated by transplanting cells generated from hES cells.The current approach of harvesting hES cells, however, entails the destruction of the extracted embryo. In light of this and other moral issues, in August 2001, President George W. Bush discontinued federal funding of all research on future stem cell lines. Published this August in the journal Nature, Dr. Robert Lanza examined the ethical issues of a new technique for deriving hES cell lines. {/description}