In addition to RCAD, other common renal disorders associated with HNF1B include Congenital Anomalies of the Kidney and Urinary Tract (CAKUT) [2,3] and Autosomal Dominant Tubulointerstitial Kidney Disease type HNF1B (ADTKD-HNF1B) [28] These are frequently associated with electrolyte disturbances such as hyperuricemia and hypomagnesemia [14,15,19,20,22]. The gene discussed is HNF1B; the disease is familial primary hypomagnesemia.