Dysfunction of the polycystin proteins leads to a reduction in intracellular calcium levels and a consequent rise in intracellular cyclic adenosine monophosphate (cAMP) levels due to the activation of calcium-inhibitable adenylyl cyclase 6 (AC6) and reduced activity of the calcium-dependent cAMP-dependent phosphodiesterases (PDE1/4c).8 This increase in cAMP, in turn, leads to alterations in cell proliferation, apoptosis, cell–cell and cell–matrix interactions, and cell polarity.8 These events are known contributors to cyst initiation and cyst growth progression. This evidence concerns the gene ADCY6 and cyst.