1. A method of diagnosing prostate cancer in a prostate tissue sample comprising: forming a spatial layout of tiles, each tile corresponding to a representative reference element in a mosaic; mapping observed elements of a prostate tissue sample onto the spatial layout of tiles of representative reference elements, the observed elements comprising gene expression levels in a prostate tissue sample; assigning a respective value to each respective tile of the spatial layout of representative reference elements; and displaying, using a graphics engine, an image of the spatial layout of tiles of representative reference elements, wherein each tile comprises atomic attributes of representative elements.