Analyzing the Circuitry of Stem Cells - New York Times: "How are the 25,000 genes of a human cell controlled and orchestrated? How does a stem cell in the embryo develop into a mature cell of the brain or heart or liver? A possibly deep insight into all these questions has been gained by mapping the top-level circuitry that controls the human embryonic stem cell.
Scientists at the Whitehead Institute in Cambridge, Mass., have developed a technique for uncovering the interactions of transcription factors. These are the agents that switch genes on or off in the cell. By figuring out these interactions on a genomewide scale, they have reconstructed the top level of the controls that govern a human embryonic stem cell."

Commentary: this line of research can change everything in medicine.