[HLA class I antigens: from molecular-genetic analysis to their role in the etiopathogenesis of various rheumatic diseases].

The published data on the structure and chromosomal localization of HLA-system, structure of HLA-genes of the I class are presented. The possible mechanisms are discussed for formation of allelic polymorphism of transplantation antigens. Some approaches to study the relation of their structure and function are also discussed. The data are reviewed on the connection of HLA-B27 antigen with a rheumatic disease (ankylosing spondylarthritis). Two groups of hypothesis explaining the latter connection are discussed. The necessity and ability to use molecular-genetic approaches to define the role of HLA-B27 antigen in etiopathogenesis of ankylosing spondylarthritis are grounded. Using the disease as a model one can elaborate the approaches to study the molecular mechanisms of predisposition to diseases having unbalanced linkage with HLA-antigens.