SLC34A1 and Hypercalciuria: Loss-of-function variants in SLC34A1 and SLC34A3 are the cause of two rare phosphate-wasting disorders, idiopathic infantile hypercalcemia type 2 (IIH, OMIM #616963) [16,17] and hereditary hypophosphatemic rickets with hypercalciuria (HHRH, OMIM #241530) [18,19,20], respectively.