Roger is a pioneer and thought leader in the field of human stem cell biology. His lab was the first to isolate pluripotent epiblast stem cells from the epiblast layer of the developing mammalian embryo. In addition, he developed one of the first cellular reprogramming protocols. Roger was co-founder of the Cambridge Stem Cell Institute. His lab is currently focused on differentiation of pluripotent stem cells, with potential applications for drug discovery, toxicity testing and cell therapies.