Two male Ap2s1L15/L15 mice did survive into adulthood, and both had more severe hypercalcaemia than their male Ap2s1+/L15 litter-mates (Supplementary Material, Table S4), thereby also indicating a dosage effect of the mutant Leu15 Ap2s1 allele on plasma calcium concentrations. Here, AP2S1 is linked to Hypercalcemia.