Any autosomal dominant polycystic kidney disease in which the cause of the disease is a mutation in the ALG9 gene. The disease is Monarch Disease Ontology term MONDO_0700000 (ALG9-associated autosomal dominant polycystic kidney disease). Also known as: ALG9 autosomal dominant polycystic kidney disease, ALG9 related autosomal dominant polycystic kidney disease, ALG9-associated ADPKD, Autosomal Dominant Polycystic Kidney Disease - ALG9, autosomal dominant polycystic kidney disease caused by mutation in ALG9.