Abstract: The present invention relates to methods of analysing gene expression, metabolite or protein levels, the use of such methods to generate distinctive profiles of a cell, and the use of such profiles in the diagnosis of disease and mode of action of novel compounds used in the treatment of a cell. These simplified methods of obtaining molecular profiles of a cell have the advantage that they allow the skilled man to produce a profile of the levels of a chosen class of molecules in a cell, which may be used to distinguish between different treatments or different cellular states, whilst being produced from fewer data than are typically used in the production of existing profiles.