The Tsc2+/- mouse is a good model for TSC related kidney disease because it is genetically similar to the majority of those with TSC, it develops age related kidney tumors (cystadenomas), and the mTOR pathway defect that occurs in the kidney tumors of Tsc2+/- mice is similar to that observed in human TSC related tumors [20-23]. The gene discussed is TSC2; the disease is tuberous sclerosis.