Within the “two-hit hypothesis” of ADPKD (which proposes that for cystogenesis to occur, a cell must possess both an inherited germline and a somatically acquired PKD1/2 mutation [61]), WT9-7 cells represent those cells possessing only the germline mutation, while WT9-12 cells represent those having acquired a second somatic hit. Here, PKD1 is linked to autosomal dominant polycystic kidney disease.