We have made significant progress on our work designed to improve differentiation from human pluripotent stem cells. Starting with an extensive characterization of the differences between tissue and pluripotent derived neural cells, we identified a list of candidates of important molecular differences between cells born in tissue versus those born in a cell culture dish. In the last three years we have systematically been testing those candidates with the highest potential to alter differentiation potential. This has led to the discovery of a handful of genes that affect transcription of other genes. Among these is a gene that is important to regulate how a cell responds to the level of oxygen in culture. We found that the level of oxygen in culture can in fact affect the differentiation potential of human pluripotent stem cells. This important observation is significant because it allows researchers a simply tool to alter differentiation and make different types of cells more quickly. Building on this, we found two small molecules with the ability to mimic fluctuations in oxygen levels, and therefore provide a very simple tool to affect differentiation. We are now in the process of combining various tools together to see if human pluripotent derived cells can be made even more similar to their tissue derived equivalents.