Familial Hypocalciuric Hypercalcemia Genetics

We identified members (10 affected and 8 unaffected) of four generations of a kindred with familial hypocalciuric hypercalcemia type 2 (referred to in other studies as Kindred 11675)^{10 (link)-12 (link)} and 9 unrelated patients with familial hypocalciuric hypercalcemia who did not have CASR or AP2S1 mutations of the coding region and exon–intron boundaries (Table S1 in the Supplementary Appendix). We also identified 8 unrelated patients with hypocalcemia and low or normal serum parathyroid hormone concentrations — findings that were consistent with autosomal dominant hypocalcemia type 1 — who did not have CASR mutations of the coding region and exon–intron boundaries (Table 1, and Table S2 in the Supplementary Appendix).^{1 (link),5 (link),9 (link),14 (link)} Informed consent was obtained from all persons (verbal consent from 82 persons and written consent from 8 persons) with the use of protocols approved by local and national ethics committees.