HLA-DRB1 and rheumatoid arthritis: In RA, key biomarkers include autoantibodies like Rheumatoid Factor (RF), Anti-Citrullinated Protein Antibodies (ACPAs), and Anti-Carbamylated Protein Antibodies (anti-CarP), as well as inflammatory markers (e.g., C-reactive protein (CRP), erythrocyte sedimentation rate (ESR)) and RA-associated genetic factors, such as specific Human Leukocyte Antigen-DR Beta 1 (HLA-DRB1) alleles [5,6,7].