PKHD1 and autosomal recessive polycystic kidney disease: Several studies support this: (1) García-González and colleagues reported genetic interaction between ADPKD and ARPKD genes in a common pathway (17), (2) it has been reported that ADPLD genes (Prkcsh and Sec63), ARPKD gene (Pkhd1) and ADPKD gene (Pkd1) interact with each other suggesting a central role of PC1 in cystogenesis (65), and (3) a developmental window for cystogenesis has been identified, suggesting that timing of secondary events may influence the severity of ADPKD (66).