This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolic disorders, Subject name: Pediatrics
The gene for Wilson&;s disease is on 
Select and explain. 
A. Long arm of Chromosome 13, B. Long arm of Chromosome 6, C. Sho arm of Chromosome 13, D. Sho arm of Chromosome 6
A: Long arm of Chromosome 13
Answer: A: Long arm of Chromosome 13 
Explanation: In Wilson&;s disease,the underlying defect lies in the long arm of chromosome 13 where there is a mutation in ATP7B gene,the normal hepatic copper- excreting gene.Eventually,capacity of hepatocytes to store copper is exceeded and copper is released into circulation which then gets deposited in extrahepatic tissues such as the brain eyes, and others. Reference:Textbook of pathology-Harsh Mohan,6th edition,page no:628