Susceptibility to polycystic kidney disease-9 (PKD9) is characterized by onset of a relatively mild form of slowly progressive renal disease in adulthood (range thirties to eighties). Affected individuals typically have large uni- or bilateral renal cysts, asymmetric kidney size, and limited renal insufficiency (decreased GFR). Some individuals may have liver cysts on imaging. Most older individuals have hypertension. End-stage kidney disease is rare. The transmission of the disorder in families shows incomplete penetrance, age-dependent penetrance, and variable expressivity. [From OMIM]