Idiopathic hypercalciuria is determined by polymorphic variants/mutations of the calcium sensing receptor (CASR) gene (4–6), mutations of SLC34A1, and SLC34A4 genes (7, 8), polymorphic variants of claudins (9), genes involved in calcium reabsorption at the tubular level. The gene discussed is CASR; the disease is Hypercalciuria.