Learn / FMK
Every FMK condition
299 diseases, deficiencies, toxicities and drug mechanisms harvested from every FMK deck — the ones sprinkled through a single bullet as much as the ones with their own slide. Pick what you're given and what you have to name, or let it cycle; distractors come from the same category so you have to discriminate (hypoketotic vs. ketotic hypoglycemia, which GSD, which urea-cycle enzyme…). Every answer shows the whole card with the lecture and slide.
Nucleotide · FMK 08.1
PRPP synthetase superactivity (primary hyperuricemia from overproduction) X-linked recessive
Defect / target: Gain-of-function mutation in PRPP synthetase
Mechanism: Excess PRPP drives more flux through GPAT (the committed step of purine synthesis) because PRPP concentration is the positive driver of de novo purine synthesis, so purine overproduction leads to overproduction of uric acid.
↑ Accumulates: PRPP, purine nucleotides, uric acid
Presentation: Early-onset hyperuricemia, gout, uric acid stones
Labs: Elevated serum uric acid (overproducer)
Treatment: Allopurinol (xanthine oxidase inhibitor)
PRPP is the shared 'green light' for both purine and pyrimidine synthesis; losing the PRPP control layer drives purine overproduction
Learn the mechanism: Purine synthesis & salvage →
FMK 08.1 Nucleic Acid Metabolism · slide 8, 12, 19