These findings contrast with other monogenic FHH mouse models; for example Casr+/− and Gna11+/− mutant mice, which are respective models for FHH1 and FHH2, typically have milder hypercalcaemia with plasma or serum calcium concentrations that are <10% above that of the WT values (19,25). This evidence concerns the gene CASR and Hypercalcemia.