This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Inflammatory bowel disease, Subject name: Surgery
Crohn's disease is associated with: 
Select and explain. 
A. NOD-2/CARD-15 gene, B. P53 suppressor gene, C. Philadelphia chromosomes, D. BRCA-1 gene
A: NOD-2/CARD-15 gene
Answer: A: NOD-2/CARD-15 gene 
Explanation: Etiology : Unknown Infectious agents proposed as potential causes: Mycobacterium paratuberculosis and measles virus IBD-1 (chromosome 16q) Relatively specific for Crohn's disease IBD-2 (chromosome 12q) More common in Ulcerative colitis on 16q CARD-15/NOD2 mutation lead to CD