Biochemistry Decarboxylation of valine, leucine and isolucine is defective in which of the following conditions? A Maple Syrup urine disease B Hanup disease C Alkaptonuria D GM1 Gangliosidosis 💡 Explanation Decarboxylation of valine, leucine and isolucine is defective in which of the following conditions? ✓ Correct Answer: A. Maple Syrup urine disease