Metabolism USMLE Step 1 Practice Question
A 3 week old male infant is brought in for poor visual tracking. He was born at term and has been feeding well on formula. Examination reveals bilateral cataracts but no jaundice, hepatomegaly, or lethargy. Urine testing is positive for reducing substances. Which of the following is the most likely deficient enzyme?
Answer choices
- AGlucose 6 phosphatase
- BFructokinase
- CGalactose 1 phosphate uridyltransferase
- DGalactokinaseCorrect answer
- EBranching enzyme
- FUDP-galactose-4-epimerase
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