PKD1 and autosomal dominant polycystic kidney disease: The studies “A Possible Founding PKD2 Mutation Associated with Variable Phenotypes of ADPKD in Bergamo Province” and “Clinical and Molecular Description of PKD1 and PKD2 Mutation Negative Carriers in ADPKD” offer valuable insights into the phenotypic variability and genetic complexity of ADPKD, while also identifying new therapeutic and diagnostic targets.