Metabolism USMLE Step 1 Practice Question
A 14 year old boy is evaluated after a deep venous thrombosis. He is tall and thin with long extremities. Slit lamp examination shows downward and inward displacement of the lens. He has mild intellectual disability. Which of the following enzyme deficiencies is the most likely cause of this patient's disorder?
Answer choices
- ACystine transporter
- BPhenylalanine hydroxylase
- CFibrillin 1
- DCystathionine beta synthaseCorrect answer
- ETyrosinase
- FMethionine synthase
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