Congenital syndrome characterized by a spectrum of malformations including the absence of the THYMUS and PARATHYROID GLANDS resulting in T-cell immunodeficiency and HYPOCALCEMIA. Other features include defects in the outflow tract of the HEART and craniofacial anomalies (velocardiofacial syndrome). Most cases result from a deletion of chromosome 21q11.2 or mutation in the TBX1 gene.
