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Array Comparative Genomic Hybridization Array CGH for Detection of Genomic Copy Number Variants

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22q11.2 deletion syndrome.

Donna M McDonald-McGinn¹, Kathleen E Sullivan², Bruno Marino³

¹Division of Human Genetics, 22q and You Center, and Clinical Genetics Center, The Children's Hospital of Philadelphia and the Department of Pediatrics at the Perelman School of Medicine at the University of Pennsylvania, 34th Street and Civic Center Boulevard, Philadelphia, Pennsylvania 19104, USA.

Nature Reviews. Disease Primers

|May 19, 2016

Summary

22q11.2 deletion syndrome (22q11.2DS) is a common microdeletion disorder. Early diagnosis through universal screening is crucial for improving patient outcomes and understanding associated conditions.

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Area of Science:

Genetics
Developmental Biology
Medical Genetics

Background:

22q11.2 deletion syndrome (22q11.2DS) is the most frequent chromosomal microdeletion.
Historically linked to DiGeorge syndrome, it presents a broad spectrum of congenital anomalies and later-onset conditions.
Management necessitates a comprehensive multidisciplinary approach.

Purpose of the Study:

To highlight the heterogeneity and broad clinical spectrum of 22q11.2DS.
To emphasize the importance of early diagnosis and universal screening for improved outcomes.
To establish 22q11.2DS as a model for studying congenital anomalies and associated disorders.

Main Methods:

Literature review and synthesis of clinical findings related to 22q11.2DS.
Analysis of diagnostic challenges stemming from clinical variability and testing familiarity.
Discussion of the implications for patient management and research.

Main Results:

22q11.2DS presents with diverse anomalies including palatal, renal, gastrointestinal, autoimmune, cognitive, behavioral, and psychiatric issues.
Diagnosis is often delayed due to lack of recognition and familiarity with genetic testing.
Early prenatal or neonatal diagnosis can significantly improve outcomes.

Conclusions:

22q11.2DS requires a multidisciplinary approach for effective management.
Universal screening is vital for timely diagnosis and intervention.
The syndrome serves as a valuable model for understanding a wide range of developmental and medical conditions.