22q11.2 distal deletion syndrome

22q11.2 distal deletion syndrome is a rare genetic condition caused by a small missing part of chromosome 22. It appears to be a recurrent genomic disorder distinct from 22q11.2 deletion syndrome, which is also known as DiGeorge syndrome and velocardiofacial syndrome. The first published description of a person with a 22q11.2 distal deletion was in 1999, and hundreds of cases have since been reported worldwide. It seems to occur equally often in males and females. Some carriers are unaffected and only discover the deletion after their child is diagnosed, so the deletion can be silent and it is unknown how many people carry a silent form.