Molecular Biology/Genetics USMLE Step 1 Practice Question
A 5-year-old girl presents with severe intellectual disability, ataxic gait, unprovoked frequent laughter, and recurrent seizures. Vital signs are stable (BP 95/60, HR 88, RR 20, Temp 37°C). On examination, she has a wide-based gait and hyperreflexia; no facial dysmorphism is noted. MRI shows mild cerebral atrophy. Genetic testing reveals deletion of the maternal chromosome 15q11-q13 region. EEG demonstrates characteristic 2-3 Hz spike-and-wave patterns. Which diagnosis best explains this clinical presentation?
Answer choices
- AAngelman syndromeCorrect answer
- BPrader Willi syndrome
- CRett syndrome
- DFragile X syndrome
- ECri du chat syndrome
- FWilliams syndrome
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