Over the past few years, different renal polycystic disorders with similar structural alterations have been detected in divergent diseases that include six forms of ADPKD (PKD1, PKD2, GANAB, DNAJB11) and ARPKD (PKHD1, DZIP1L), 15 types of MKS, medullary cystic kidney diseases 1 and 2 (MUC1 and MCKD2), CYSRD, congenital anomalies of the kidney and urinary tract 1‐3 (CAKUT1‐3), polycystic liver disease 1‐4 (PCLD1‐4) and nephronophthisis 1‐17. The gene discussed is PKHD1; the disease is nephronophthisis.