General Pathology USMLE Step 1 Practice Question
A 14-year-old boy presents with multiple café-au-lait macules, axillary freckling, and cutaneous neurofibromas. Vital signs are normal (BP 118/76, HR 82, RR 16, Temp 37°C). His mother has identical findings. Genetic testing confirms NF1 gene mutation. MRI shows no optic pathway gliomas. The patient denies vision changes or skeletal abnormalities. Which signaling protein does the mutated NF1 gene normally downregulate?
Answer choices
- AABL
- BRASCorrect answer
- CSMAD4
- DJAK2
- EALK
- FF. EGFR
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