HNF1B and autosomal dominant polycystic kidney disease: Moreover, some phenotypes of cystic kidney disorders e.g., ADPKD, ARPKD, NPHP and HNF1β-related disease may overlap (e.g. cystic expansion of the kidneys, kidney enlargement, liver fibrosis, situs inversus), making the identification of causative genes and mutations a complex and expensive process.