PKD2 and cystic kidney disease: These patients had more novel variants in PKD1 or PKD2 or a variant in another cystic kidney disease gene (ALG8, GANAB, IFT140, or PKHD1).6 In a large Taiwanese ADPKD cohort study, pathogenic PKD1 or PKD2 variants were identified in 69% of families, with 7% due to PKHD1, GANAB, or ALG8.