Biochemistry Pruritis (Itching) is caused by deficiency of – A HMB synthase B 5-ALA dehydratase C Uroporphyrinogen - I synthase D Uroporphyrinogen - III synthase 💡 Explanation Pruritis (Itching) is caused by deficiency of - ✓ Correct Answer: D. Uroporphyrinogen - III synthase