In a first-of-its-kind study, a research team from the Perelman School of Medicine at the University of Pennsylvania was able to grow adult human neurons donated from patients who had undergone surgery. From these cell cultures, they identified more than five brain cell types and the potential proteins each cell could make. The research aligns with the goals of the national BRAIN Initiative to create a complete census neuronal cells in the brain. The characterizing feature of a neuronal cell is it’s transcriptome, referring to those genes that are transcribed into RNA to make working proteins, which differ from cell to cell. This breakthrough should lead to more and better information about neuronal functions. Bravo!