Relationship of genetic polymorphism of the acute phase marker of inflammation rs12218 of the SAA1 gene with clinical phenotypes of juvenile idiopathic arthritis

Objective : to test the hypothesis of a possible relationship between the rs12218 polymorphism of the SAA1 gene and a predisposition to different clinical phenotypes of juvenile idiopathic arthritis (JIA). Patients and methods . Genetic typing of rs12218 polymorphism was carried out in 142 children: 77 of them were diagnosed with JIA, including 30 patients with oligoarthritis (oJIA), 20 with polyarthritis (pJIA), and 27 with systemic onset (sJIA). Sixty five healthy volunteers were included in the control group. The rs12218 polymorphism of the SAA1 gene was investigated using real-time polymerase chain reaction. Results and discussion . A high risk of developing the clinical phenotype of oJIA in carriers of the C mutant allele of the rs12218 T/C polymorphism of the SAA1 gene was established. Statistically significant differences between the clinical phenotypes of oJIA and sJIA in the frequency distribution of genotypes and alleles of rs12218 T/C polymorphism of the SAA1 gene are shown. Conclusion . The results of the studies have confirmed the important role of the rs12218 T/C polymorphism of the SAA1 gene in the formation of susceptibility to clinical variants of JIA.