A child presents with intellectual disability, elf-like facies, hypercalcemia, and a friendly 'cocktail party' personality. Genetic testing reveals deletion of the elastin gene region. This is consistent with:
- A Prader-Willi syndrome
- B Angelman syndrome
- C Williams syndrome (7q11.23 microdeletion) ✓
- D Cri-du-chat syndrome
Correct answer: C. Williams syndrome (7q11.23 microdeletion)
Explanation
Williams syndrome results from a microdeletion at 7q11.23 encompassing the elastin (ELN) gene and about 25 others. Features include supravalvular aortic stenosis (due to elastin deficiency), elfin facies, intellectual disability, hypercalcemia, and a distinctive hypersocial (cocktail party) personality with preserved language skills. Prader-Willi and Angelman syndromes involve chromosome 15; cri-du-chat is due to 5p deletion.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.