In some rare cases of autosomal dominant or recessive hypoparathyroidism, namely Familial Isolated Hypoparathyroidism, type 1 (FIH) (MIM 146200) patients present by heterozygous, homozygous, or compound heterozygous mutation in the PTH gene (11p15.3-p15.1) coding for the prepro-PTH peptide. The gene discussed is PTH; the disease is hypoparathyroidism.