This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Inborn Errors of Metabolism, Subject name: Pediatrics
Wilson's disease is caused by defect in: 
Select and explain. 
A. ATP 7A mutation, B. ATP 7B mutation, C. Ceruloplasmin, D. ATP 7C mutation
B: ATP 7B mutation
Answer: B: ATP 7B mutation 
Explanation: b. ATP 7B mutation(Ref: Nelson's 20/e p 1939-1940, Ghai 8/e p 320-321)The abnormal gene for Wilson disease is ATP7B on long arm of chromosome 13 (13q14.3)