<unk>  is estimated to affect between one in 2000 and one in 4000 live births. This estimate is based on major birth defects and may be an underestimate, because some individuals with the deletion have few symptoms and may not have been formally diagnosed. It is one of the most common causes of intellectual disability due to a genetic deletion syndrome. The number of people affected has been expected to rise because of multiple reasons: (1) surgical and medical advances, an increasing number of people are surviving heart defects associated with the syndrome. These individuals are in turn having children. The chances of a person with<unk>  having an affected child is 50% for each pregnancy; (2) Parents who have affected children, but who were unaware of their own genetic conditions, are now being diagnosed as genetic testing become available; (3) Molecular genetics techniques such as FISH (fluorescence in situ hybridization) have limitations and have not been able to detect all 22q11.2 deletions. Newer technologies have been able to detect these atypical deletions.
DiGeorge syndrome
Smith–Lemli–Opitz syndrome
Langer–Giedion syndrome
Alagille syndrome
ATR-16 syndrome
Goldenhar syndrome
ATR-X syndrome
VACTERL association