Nucleotide metabolism: Lesch-Nyhan syndrome: practice question

The best answer is D, Hypoxanthine-guanine phosphoribosyltransferase. HGPRT deficiency prevents salvage of hypoxanthine and guanine, increasing de novo purine synthesis and uric acid production.

DHFR is inhibited by methotrexate.

ADA deficiency causes a form of severe combined immunodeficiency.

Xanthine oxidase converts hypoxanthine and xanthine to uric acid.

It tests Nucleotide metabolism: Lesch-Nyhan syndrome in Biochemistry. Neurologic dysfunction and self-mutilation are characteristic.

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

Build one table of enzyme deficiency, disease, inheritance and key finding, then revise it by spaced recall. Then use the flashcards and the other Biochemistry questions on this site to test what stuck.

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.