<prompt> Thymic hypoplasia is seen in which of the following?Wiskott-Aldrich syndromeDigeorge syndromeIgA deficiencyAgammaglobulinemia  <response>: DiGeorge syndromeThymic hypoplasiaVelocardiofacial syndrome T cell deficiency Failure of devt of 3rd 4th pharyngeal pouches Individuals have Variable loss of T cell mediated immunity - hypolastic thymus Tetany - lack of parathyroids Congenital defects of hea great vessels T cell zones of lymphoid organs are depleted Deletion of gene mapped to chr 22q11 