TY - CHAP M1 - Book, Section TI - 22q11.2 Deletion (DiGeorge Syndrome) A1 - Bianchi, Diana W. A1 - Crombleholme, Timothy M. A1 - D'Alton, Mary E. A1 - Malone, Fergal D. Y1 - 2015 N1 - T2 - Fetology: Diagnosis and Management of the Fetal Patient, 2e AB - Key PointsMost common microdeletion syndrome reported in humans.22q11.2 deletion is associated with DiGeorge syndrome, velocardiofacial syndrome (VCFS), Opitz G/BBB syndrome, and Cayler cardiofacial syndrome (also known as asymmetric crying facies syndrome).Incidence is 1 in 6000 livebirths.Deletion is associated with specific types of congenital heart disease, including tetralogy of Fallot, truncus arteriosus, absent pulmonary valve, and aortic arch abnormalities.Other associated sonographic findings include growth restriction, nuchal translucency, thymic hypoplasia, and renal anomalies. The presence of polyhydramnios is predictive of postnatal feeding difficulties.Once the deletion is found, both parents should also undergo cytogenetic analysis.Delivery should occur in a tertiary center.Affected neonates are at risk for seizure disorders due to hypocalcemia.Postnatal problems include speech defects due to palatal abnormalities, repeated infections due to immunodeficiency, developmental delay, feeding issues, and serious behavioral and psychiatric problems.22q11.2 deletion is inherited as an autosomal dominant trait.The major causative gene is TBX1, a member of the T-box protein family of genes. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/04/19 UR - obgyn.mhmedical.com/content.aspx?aid=1106402295 ER -