Gene HLA-DRB1
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Also known as
major histocompatibility complex class II DR beta 1, HLA-DR1B, MHC class II DR beta chainOverview
HLA-DRB1 (HLA Class II Histocompatibility Antigen DR Beta 1) encodes the polymorphic beta chain of the HLA-DR molecule, one of the most immunologically important MHC class II proteins. HLA-DR molecules present extracellular antigens to CD4+ helper T cells and are expressed constitutively on professional antigen-presenting cells. HLA-DRB1 is highly polymorphic with over 2,000 known alleles.HLA-DRB1 variants are strongly associated with rheumatoid arthritis, particularly the "shared epitope" alleles (DRB1*01, *04, *10). Multiple sclerosis is associated with DRB1*15:01. The gene also influences response to disease-modifying therapies and predicts outcomes in autoimmune conditions. In transplantation, HLA-DR matching significantly impacts graft survival and is prioritized in donor selection.
Understanding your HLA-DRB1 genetic status provides insights into autoimmune disease risk and transplant compatibility. This information is relevant for understanding susceptibility to rheumatoid arthritis, multiple sclerosis, and other autoimmune conditions, as well as for organ and bone marrow transplant matching.