Metabolism USMLE Step 1 Practice Question
A 2-week-old male presents with tetralogy of Fallot, cleft palate, and recurrent candidal infections. Vital signs show HR 158/min, RR 42/min, SpO2 88% on room air, and temperature 37.2°C. Laboratory studies reveal lymphocyte count of 800/μL (normal >1500/μL). Standard karyotyping is normal. Thymic shadow is absent on chest X-ray. Which chromosomal abnormality detection method most rapidly confirms the suspected microdeletion syndrome?
Answer choices
- ASouthern blot
- BNorthern blot
- CELISA
- DFluorescence in situ hybridizationCorrect answer
- EWestern blot
- FQuantitative polymerase chain reaction
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