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: Medicine
All of the following are true about Rheumatoid Ahritis, Except: 
Select and explain. 
A. HLA-DR determine genetic susceptibility, B. HLA-B27 determine genetic susceptibility, C. Anemia, D. Subcutaneous nodules
B: HLA-B27 determine genetic susceptibility
Answer: B: HLA-B27 determine genetic susceptibility 
Explanation: Answer is B (HLA-B27 determine genetic susceptibility): HLA-B27 antigen is associated with seronegative spondyloahropathies and not Rheumatoid Ahritis. RA is associated with HLA DR alleles and may present with anemia, subcutaneous nodules and joint deformities. HLA B 27 associated seronegative spondyloahropathies Ankylosing spondylitis Psoriatic ahritis Reactive ahritis (Reiter's syndrome) Enteropathic ahritis (Associated with Inflammatory Bowel disease) Undifferentiated spondyloahropathy