Microdeletion FISH - Williams-Beuren Syndrome (7q11.23)
Definition
The contiguous gene microdeletion of approximately 1.5 to 1.8 Mb in the 7q11.23 region spans the elastin (ELN) gene and approximately 25-28 surrounding genes; it is characterized by cardiovascular anomalies, most notably supravalvular aortic stenosis, a characteristic 'elfin face' appearance, hypercalcemia, and an overly sociable behavioral pattern. Its incidence is approximately 1/7,500 to 10,000.
Method
FISH analysis
Accepted sample types
Amniotic fluid, Chorionic villus, Cord blood
Inheritance
Usually de novo; when inherited, autosomal dominant.