This can be explained by the presence of essential genes of the PI3K pathway that have a remarkably poor conservation in terms of co-expression, and even more strikingly we found that the first top four diverged genes of this pathway are the crucial mTOR, PIK3R4, AKT2, FGF23. Therefore, the knowledge of the relatively few homologs that are commonly co-expressed with these genes, as reported in Additional file 2, pinpoint mouse targets to test processes such as cancer progression and glucose metabolism defects caused by the de-regulation of PI3K/Akt signalling. The gene discussed is PIK3R4; the disease is cancer.