Our project is aimed at providing limitless supplies of nerve tissue for transplantation to Parkinson’s disease patients. Transplantation of fetal brain tissue into such patients has seen significant past success, but the supplies of material are sparse and there are ethical objections to this therapy. Our goal is instead to generate dopaminergic neurons, the key brain cell that is supplied by transplants, from human embryonic stem cells. Our laboratory has been able to identify a simply synthetic chemical compound, like a conventional drug, that will convert precursors of neurons to dopaminergic neurons. These neural precursor cells are generated from human embryonic stem cells using known methods. The main reason that our approach is attractive is that past methods to force stem cells to differentiate to dopaminergic neurons have involved animal products that would make the resulting cells unsuitable for transplantation because of immune rejection.