Given that rapamycin – an mTOR inhibitor, shows efficacy in several rodent models of polycystic kidney disease [22], [34], [49] it would be interesting to determine if these renal cystoproteins act at or upstream of the PC1-TSC2 node of the pathway, implicating PC1-TSC2 as a pathogenic nexus in these disorders. The gene discussed is TSC2; the disease is polycystic kidney disease.