DiGeorge syndrome: new insights.

Most patients with the clinical features of DiGeorge, velocardiofacial, and conotruncal anomaly face syndromes share a common genetic cause, namely, a deletion of chromosome 22q11, and define the most common deletion syndrome known at this time. The clinical features of the 22q11 deletion syndrome are highly variable between individuals; some have subtle findings, whereas others are severely affected. The most common clinical features include specific types of congenital heart disease, hypocalcemia, immunodeficiency, facial dysmorphia, palate anomalies, velopharyngeal dysfunction, renal anomalies, and speech and feeding disorders as well as neurocognitive, behavioral, and psychiatric disorders. A significant number of patients with tetralogy of Fallot, truncus arteriosus, an interrupted aortic arch, isolated aortic arch anomalies, and perimembranous ventricular septal defects have a 22q11 deletion. Routine testing for a 22q11 deletion in this subset of patients should be considered to provide anticipatory medical intervention and appropriate family counseling.