Familial Isolated Hypoparathyroidism Due to Agenesis of Parathyroid Gland An important gene associated with Familial Isolated Hypoparathyroidism Due to Agenesis of Parathyroid Gland is GCM2 (Glial Cells Missing Transcription Factor 2). Affiliated tissues include eye, and related phenotypes are hypocalcemia and congenital hypoparathyroidism