There is little differential gene expression between Plasmodium yoelii 17X parasites isolated from individual mice. Three animals (M1, M2 and M3) were infected with P. yoelii 17X iRBCs from a single donor mouse. RNA was isolated on day 10 or 11 post-infection and transcripts detected using P. yoelii DNA microarrays. The three possible pair-wise comparisons are listed at the top of the figure and functional categories are listed in the far left column. Solid dark blue boxes indicate that there are no differentially expressed genes for a given comparison in a particular functional group. In cases where there are differentially expressed genes, the number of genes that are up-regulated is listed at the top half of the box; the number of down-regulated genes is listed in the bottom half of the box. Up- and down- regulation is reported with respect to the second animal listed in the column heading. For example, there is one gene down-regulated in the ‘schizont, merozoite, invasion’ category in mouse 3 with respect to mouse 2. The total number of genes that were up- or down-regulated is indicated at the bottom of the Figure.