Specific HLA alleles include HLA-DR3 and HLA-DR4 (associated with type 1 diabetes—T1D), as well as HLA-DRB1 (associated with rheumatoid arthritis—RA and multiple sclerosis—MS), HLA-DQB1 (associated with MS), and HLA-B27 (associated with AS) [37,38,39]. Here, HLA-DRB1 is linked to rheumatoid arthritis.