Additionally, 22q11 microdeletion syndrome mainly manifests as cardiac malformation, a cleft palate, hypocalcemia, thymic dysplasia, facial abnormalities, etc. The deleted key gene (TBX1) may be involved in developing the sixth arched artery; it may also be involved in the junction between the peripheral and central pulmonary arteries. The gene discussed is TBX1; the disease is Hypocalcemia.