My research on Parkinson's disease is in two major areas. First is transplantation of dopamine neurons into patients. We started transplanting cells into humans in 1988. We are now generating dopamine neurons from stem cells and expect to be transplanting those cells into people in the next few years. Our second area of research is stopping the progression of Parkinson's disease by turning on a protective gene in the brain. We have found that the drug phenylbutyrate can upregulate the gene in the brain of animals and stop Parkinson's from developing in a transgenic mouse model of the disease. We are beginning tests of the drug in patients.