TRPV5 mutation; Klotho deficiency; hereditary dRTA (SLC4A1, ATP6V1B1 or ATP6V0A4, FOXI1, WDR72 and CA2 mutation); Pseudoxanthoma elasticum (PXE, ABCC6 mutation). The gene discussed is ATP6V1B1; the disease is Pseudoxanthoma elasticum.