Contribution of genetic studies in rodent models of autoimmune arthritis to understanding and treatment of rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic and potentially debilitating autoimmune disease. While novel therapies have emerged in recent years, disease remission is rarely achieved. RA is a complex trait, and the identifying of its susceptibility and severity genes has been anticipated to generate new targets for therapeutic intervention. However, finding those genes and understanding their function has been a challenging task. Studies in rodent intercrosses and congenics generated from inbred strains have been an important complementary strategy to identify arthritis genes, and understand how they operate to regulate disease. Furthermore, these new rodent arthritis genes will be new targets for therapeutic interventions, and will identify new candidate genes or candidate pathways for association studies in RA. In this review-opinion article I discuss RA genetics, difficulties involved in gene identification, and how rodent models can facilitate (1) the discovery of both arthritis susceptibility and severity genes, (2) studies of gene–environment interactions, (3) studies of gene–gender interactions, (4) epistasis, (5) functional characterization of the specific genes, (6) development of novel therapies and (7) how the information generated from rodent studies will be useful to understanding and potentially treating RA.