Molecular Biology/Genetics USMLE Step 1 Practice Question
A 9-year-old boy is brought to his pediatrician by his parents who report that he has had difficulty maintaining academic performance despite previous normal development. On examination, he is at the 5th percentile for height, has mild dysmorphic facial features including a broad forehead and hypertelorism, and demonstrates friendly but overly social behavior with examiners. Developmental history is significant for delayed speech and mild motor coordination difficulties. His cardiac examination reveals a systolic murmur at the right upper sternal border that does not change with Valsalva maneuver. Genetic testing reveals a microdeletion of chromosome 7q11.23. Which of the following is the most likely additional finding in this patient?
Answer choices
- AThymic hypoplasia with T-cell deficiency
- BMicrognathia and glossoptosis
- CInfantile spasms and hypsarrhythmia on EEG
- DSupravalvular aortic stenosis with pulmonary artery stenosisCorrect answer
- EAtrial septal defect with left-to-right shunt
- FMitral valve prolapse with aortic regurgitation
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