Which enzyme's deficiency is associated with the disease homocystinuria?

A Cystathionine beta-synthase ✓
B Methionine synthase
C Homocysteine methyltransferase
D Betaine homocysteine methyltransferase

Explanation

Cystathionine beta-synthase is an enzyme involved in the metabolism of homocysteine. Its deficiency leads to the accumulation of homocysteine, causing the disease homocystinuria.

Source

Biochemistry textbooks
Enzymes in Disease Biochemistry Amino Acid Metabolism Disorders Hard MEDICAL Confidence: high