Northwestern scientists found the master gene switch that programs the ear hair cells is TBX2. When it is expressed, the cell becomes an inner hair cell. When blocked, the cell becomes an outer hair cell. Jaime García-Añoveros, professor of Anesthesiology, Neurology and Neuroscience at Northwestern and the study’s lead author, said that producing these cells will require a gene cocktail. First, ATOH1 and GF1 are necessary to make a cochlear hair cell from a non-hair cell. Then the TBX2 would be turned on or off to produce the needed inner or outer cell. The goal would be to reprogram supporting cells into outer or inner hair cells. These supporting cells are interlaced among the hair cells and provide them with structural support