A newborn has a conotruncal heart defect (tetralogy of Fallot), cleft palate, and hypocalcemia. Which chromosomal abnormality is most likely responsible?
- A Deletion 5p
- B Deletion 13q14
- C Deletion 22q11.2 ✓
- D Trisomy 13
Correct answer: C. Deletion 22q11.2
Explanation
22q11.2 deletion syndrome (DiGeorge/velocardiofacial syndrome) classically presents with conotruncal cardiac defects (tetralogy of Fallot, interrupted aortic arch), thymic hypoplasia, cleft palate, and hypocalcemia due to parathyroid hypoplasia. Deletion 5p causes cri-du-chat syndrome. Deletion 13q14 is associated with retinoblastoma. Trisomy 13 causes holoprosencephaly, polydactyly, and midline defects, not the CATCH-22 phenotype.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.