Heterozygous variants in the calcium-sensing receptor gene CASR (pLI = 0.05) can cause hypocalciuric hypercalcemia [30] while autosomal-dominant tubulointerstitial kidney disease can be caused by variants in UMOD (pLI = 0), MUC1 (pLI = 0.02) or REN (pLI = 0) [31]. Here, MUC1 is linked to familial hypocalciuric hypercalcemia.