Overall, genes most strongly increased by CR across tissues were associated with fatty acid metabolism, the citrate cycle, PPAR signaling, oxidative phophorylation, amino acid degradation and metabolism, circadian rhythm, renal cell carcinoma, fatty acid elongation in mitochondria and the insulin signaling pathway (P < 0.01; over-represented KEGG pathways) (Additional File 5). The gene discussed is PPARA; the disease is renal cell carcinoma.