Hypocalciuric hypercalcemia type 1 (OMIM phenotype number 145980) is an AD condition resulting from an inactivating variant in CASR, resulting in lifelong mild to moderate hypercalcemia, inappropriate hypocalciuria, and normal PTH to mild hyperparathyroidism (Carling et al., 2000). This evidence concerns the gene CASR and hyperparathyroidism.