The etiology of autoimmunity diseases includes an immunological reaction against various autoantigens. The HLA
molecules play an important role in the antigen presentation process to the immune system. The HLA genes were
found as the most significant genetic predisposition factor. The strongest association described in the literature is
the association of HLA-B27 with ankylosing spondylitis. Associations were since usually observed with HLA-DR
and DQ genes. We are also focused on Diabetes mellitus 1. type. Diabetes is an organ specific autoimmune disease
characterised by destruction of beta-cells of Langerhansen pancreatic islets. The cause of the destruction process is
not known yet, but it seems to be triggered by repeated presentation of self-antigen hGAD65 to the immune system.
This review presents themost interesting solutions and hypotheses of the unanswered question about HLA association
HLA, association, autoimmunity, hypothesis, ankylosing spondylitis, HLA-B27, diabetes mellitus,
glutamic acid decarboxylase (hGAD65), enteroviruses (HERVs), regulation of gene expression.