Cells become specialised in a process called differentiation, whereby cells turn into specific types of cells with specific functions. Once a cell has differentiated into its final cell state, it usually will remain like this. However, in some instances, cells have been shown to 'erase' their functional identity and 'reprogram' to become other cells with other functions. This can occur naturally, for example in diseases like cancer. Sophie Jarriault is interested in understanding how this happens and whether this process can be harnessed for cancer treatments and regenerative medicine- where dysfunctional cells, tissues or organs are replaced or engineered to restore normal function.