This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autoimmune Diseases, Subject name: Pathology
HLA-B27 is associated with - 
Select and explain. 
A. Ankylosing spondylitis, B. Rheumatoid arthritis, C. Chronic active hepatitis, D. Diabetes
A: Ankylosing spondylitis
Answer: A: Ankylosing spondylitis 
Explanation: Ans. is 'a' i.e., Ankylosing spondylitis o HLA-B27is associated with seronegativespondyloartropathies (ankylosingspondylitis. Psoriatic arthritis, Reiter's syndrome, reactive arthritis) and acute anterior uveitis