This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
[{'content': 'A 6 year old mentally retarded male child patient presents with hepatosplenomegaly, coarse facial features, corneal clouding, large tongue, prominent forehead, joint stiffness, short stature and skeletal dysplasia. What is the enzyme deficient in this patient? \nSelect and explain. \nA. Iduronate sulfatase, B. β-Galactosidase, C. α-L- Iduronidase, D. β-Glucuronidase', 'role': 'user'}, {'content': "Answer: C \nExplanation: Mucopolysaccharidosis-I H (Hurler’s Disease):\nBiochemical defect:\nHomozygous or double heterozygous nonsense mutation of\xa0IDUA gene on Chromosome 4p encoding α-L-Iduronidase.\nClinical features of MPS I H (Hurler’s Disease):\n\nProgressive disorder with multiple organ and tissue involvement that results in premature death, usually by 10 years of age.\nAn infant with Hurler’s syndrome appears normal at birth, but inguinal hernias are often present. Diagnosis is usually made between 6 and 24 month of age.\nHepatosplenomegaly, coarse facial features, corneal clouding, large tongue, prominent forehead, joint\xa0stiffness, short stature\xa0and skeletal dysplasia are seen.\nAcute cardiomyopathy has been found in some infants < 1 year of age.\nMost patients have recurrent upper respiratory tract and ear\xa0infections, noisy breathing and persistent copious nasal discharge.\nValvular heart disease with incompetence, notably of the mitral and aortic valves, regularly develops, as dose coronary artery narrowing.\nObstructive airway disease, notably during sleep, may necessitate trachotomy. Obstructive airway disease, respiratory infection\xa0and cardiac complications are the common causes of death.\xa0\n\nKey Concept:\nHurler's disease is due to\xa0α-L- Iduronidase enzyme deficiency due to homozygous or double heterozygous nonsense mutation of\xa0IDUA gene on Chromosome 4p encoding α-L-Iduronidase.\nReference- Harper’s illustrated biochemistry. 30th edition page no: 179", 'role': 'assistant'}]