Genetics of vasculitis.

PURPOSE OF REVIEW: Evidence for a genetic contribution to risk for developing different forms of vasculitis has accumulated recently. Cohorts have been assembled that are of sufficient size to allow application of up-to-date methods of genetic analysis. This review will summarize the current understanding of the genetics of several forms of vasculitis. RECENT
FINDINGS: The first genome-wide association studies (GWAS) in vasculitis have been published, in Behçet's disease and Kawasaki disease; none of the genes identified in these studies had been previously investigated. Associations of various HLA alleles with different vasculitides have been replicated. Other genes associated with Wegener's granulomatosis in replicated candidate gene studies are also associated with other autoimmune diseases. Consistent with this finding, epidemiologic data suggest a familial link between risk of Wegener's granulomatosis and rheumatoid arthritis. Among the most interesting genes clearly associated with vasculitis, however, are uncommon alleles that also cause monogenic recessive diseases: MEFV in Behçet's disease and Henoch-Schönlein purpura, and A1AT in Wegener's granulomatosis.
SUMMARY: At the same time as candidate gene studies in vasculitis are identifying both common polymorphisms associated with other autoimmune diseases and rare alleles associated with recessive inherited diseases, early GWAS results are identifying completely different associations. The tools are available to more comprehensively delineate the genetic component of risk for these rare diseases.