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: Surgery
Ankylosing apondylitis is associated with ? 
Select and explain. 
A. HLA-B27, B. HLA-B-8, C. HLA - DW4/DR4, D. HLA - DR3
A: HLA-B27
Answer: A: HLA-B27 
Explanation: Ans. is 'a' i.e., HLA-B27 There is strong correlation with HLA-B27 90-95% of cases are positive for HLA - B27.