Autosomal dominant polycystic kidney disease: molecular genetics and pathophysiology.

In autosomal dominant polycystic kidney disease (ADPKD), the precise steps leading to cyst formation and loss of renal function remain uncertain. Pathophysiologic studies have suggested that renal tubule epithelial cells form cysts as a consequence of increased proliferation, dedifferentiation, and transition to a secretory pattern of transepithelial-fluid transport. Since the cloning of two genes implicated in ADPKD, there has been an explosion of information about the functions of the gene products polycystin 1 and 2. In this review, we discuss what is known of the functions of the polycystins and how this information is providing important insights into the molecular pathogenesis of ADPKD.