Of the more than 500 genes screened in two distinct protocols, the gene most comprehensively implicated in mediating lifespan extension by bDR was cbp: expression of CBP accounts for the most variance in lifespan, decreases with age and diabetes, is induced by bDR and by the daf-2 mutation, and cbp-1 RNAi blocks lifespan extension by all three protocols of DR examined so far and partly attenuates lifespan extension by the daf-2 mutation. The gene discussed is CREBBP; the disease is diabetes mellitus.