22q11.2 Deletion Syndrome: Copy Number Variation Analysis in Two Patients

Background: 22q11.2 deletion syndrome is the most common microdeletion syndrome. It is caused by an autosomal dominant microdeletion of chromosome 22 at the long arm 11.2 band. It is difficult to diagnose of this syndrome because of its multiple phenotypes. Methods and findings: In this study, we identified two cases of 22q11.2 deletion syndrome by array based comparative genomic hybridization (aCGH). These two cases exhibited atypical anomaly examined by aCGH and they exhibited different presentations although aCGH showed the same deletion. Conclusion: 22q11.2 deletion syndrome is a difficult diagnosed disease which could be efficiently detected by aCGH. The patients could exhibit different phenotypes even when aCGH showed the same deletion. These findings will provide useful information to better understand 22q11.2 deletion syndrome.