Cell 136, 411–419 (2009) 10.1016/j.cell.2009.01.023

For skin, liver or stomach cells to behave like embryonic stem cells, researchers have so far had to add to them at least three genes that have been linked to cancer. But only one such gene, which encodes a molecule called Oct4 (and also Pou5F1), is needed to induce pluripotency — the ability to develop into most cell types — in mouse neural stem cells.

Unlike most successful attempts to reprogram cells, which take about three weeks, this approach by Hans Schöler of the Max Planck Institute for Molecular Biomedicine in Münster, Germany, and his co-workers took four to five weeks of culturing. Nonetheless, the efficiency of the reprogramming was roughly equal to that of mouse embryonic skin cells when Oct4 and three other reprogramming factors are added to them.