22q 11.2 Distal Deletion

22q 11.2 Distal Deletion

A 22q11.2 distal deletion is a rare genetic condition caused by a tiny missing part of one of the body’s 46 chromosomes – chromosome 22. 22q11.2 distal deletion syndrome appears to be a recurrent genomic disorder distinct from DiGeorge syndrome (DGS; 188400) and velocardiofacial syndrome (VCFS; 192430).

The first published description of a person with a distal 22q11.2 deletion was in 1999. There have since been more than 50 cases reported in the medical literature worldwide. When a particular set of developmental features occurs in a recognisable and consistent pattern in enough people, as a result of a single cause, the condition is called a syndrome. The features of a distal 22q11.2 deletion do occur in this way, so the disorder is often known as 22q11.2 distal deletion syndrome. The deletion seems to occur equally often in males and females. There are reports of people who are unaffected by carrying the deletion and only discovered it after their child was diagnosed. It seems that the 22q11.2 distal deletion can be ‘silent’ and that no-one knows how many people out there have a silent form of this syndrome.