DiGeorge syndrome: new insights.

Area of Science:

• Genetics
• Medical Genetics
• Human Genetics

Background:

• DiGeorge, velocardiofacial, and conotruncal anomaly face syndromes share a common genetic cause: deletion of chromosome 22q11.
• This 22q11 deletion represents the most prevalent known deletion syndrome.
• Clinical manifestations of 22q11 deletion syndrome exhibit significant inter-individual variability, ranging from subtle to severe.

Purpose of the Study:

• To highlight the genetic basis of several distinct clinical syndromes.
• To emphasize the variability and common features of 22q11 deletion syndrome.
• To advocate for routine genetic testing in specific congenital heart defect populations.

Main Methods:

• Clinical observation and genetic analysis were implicitly used to define the syndrome.
• Review of clinical features associated with 22q11 deletion.
• Analysis of the prevalence of 22q11 deletion in patients with specific congenital heart defects.

Main Results:

• A deletion on chromosome 22q11 is the shared genetic cause for DiGeorge, velocardiofacial, and conotruncal anomaly face syndromes.
• Common clinical features include congenital heart disease, hypocalcemia, immunodeficiency, facial dysmorphia, palate anomalies, velopharyngeal dysfunction, renal anomalies, and neurodevelopmental disorders.
• A significant proportion of patients with tetralogy of Fallot, truncus arteriosus, interrupted aortic arch, and perimembranous VSDs have a 22q11 deletion.

Conclusions:

• The 22q11 deletion syndrome is a common and highly variable genetic disorder.
• Routine 22q11 deletion testing is recommended for patients with specific congenital heart defects.
• Early diagnosis facilitates anticipatory medical intervention and family counseling.