The pathogenesis, clinical course, and response to treatment in systemic juvenile idiopathic arthritis (SJIA) differ from other types of juvenile idiopathic arthritis and are similar to other interleukin-1 (IL-1)-mediated diseases.
Genomic DNA of 55 Iranian patients with JIA and 140 controls were extracted and typed for IL-1α gene at position -889, IL-1β gene at positions -511 and +3962, IL-1R gene at position Pst-I 1970, and interleikin-1 receptor antagonist (IL-1Ra) gene at position Mspa-I 11100, using polymerase chain reaction with sequence-specific primers method, and compared between patients and controls.
To investigate the genetic contribution of cytokine gene polymorphisms (interleukin 1 (IL1) and tumour necrosis factor alpha (TNFalpha)) on disease phenotype and on response to TNF-blocking agents in a population of patients with juvenile idiopathic arthritis (JIA).
It also underlines the genetic contribution of IL-1 polymorphisms to the pathogenesis of JIA, as another polymorphism within the IL-1beta may influence the risk of the disease.
Interaction between HLA-DR and HLA-DP, and between HLA and interleukin 1 alpha in juvenile rheumatoid arthritis indicates heterogeneity of pathogenic mechanisms of the disease.