DiGeorge syndrome is also known as 22q11.2 deletion syndrome,DiGeorge anomaly, velocardiofacial syndrome (VCFS), Shprintzen syndrome, conotruncal anomaly face syndrome (CTAF) or Takao syndrome, Sedlackova syndrome, Cayler cardiofacial syndrome,Strong syndrome, congenital thymic aplasia, and thymic hypoplasia. This syndrome is caused by the deletion of a small piece of chromosome 22. As such, it is recommended that the name ""22q11.2 deletion syndrome (22q11.2DS)"" be used.22q11.2DS is the most common microdeletion syndrome characterized by low copy repeats and the deletion occurs near the middle of the chromosome at a location designated 22q11.2—signifying its location on the long arm of one of the pair of chromosomes 22, on region 1, band 1, sub-band 2. The inheritance pattern is autosomal dominant and it has a prevalence estimated at 1:4000. The syndrome was described in 1968 by the pediatric endocrinologist Angelo DiGeorge. 22q11 deletion is also associated with truncus arteriosus and tetralogy of Fallot.