The Tsc2+/- A/J mouse is heterozygous for deletion of exons 1-2 and is considered a good model to study TSC-related kidney disease because the mice develop age-related renal cysts and kidney tumors (cystadenomas and cystadenocarcinomas) with a defective mTOR pathway like that observed in human TSC-related tumors (9–11). Here, TSC2 is linked to cystadenoma.