Background Juvenile idiopathic arthritis (JIA) – is a chronic systemic autoimmune disease that is a characterized by articular lesion with synovial hyperplasia and cellular infiltration. One of the pathogenetic mechanisms of development of the disease is reducing of the sensitivity of cells to apoptosis, which leads to proliferation and hyperplasia of synoviocytes, maintaining a pool of antigen-presenting cells, T-cells and chronicity inflammation (S.Gay et al 1993, U. Muller-Ladner et al 2007). There are many mechanisms leading to decrease cellular apoptosis, the chief of these functional changes in protein P53. Arg72Pro exon 4 and ins/del 16bp intron 3 polymorphisms are associated with affects the functional activity of the protein P53 (P.Dumont et al, 2003).

Objectives We investigated polymorphism gene P53 exon 4 Arg72Pro and intron 3 ins/del 16 bp in children with JIA in order to identify the influence of gene polymorphisms in the variant of the course and outcome of the disease.

Methods We examined 95 children with JIA. Children were divided into several groups by the sex, different variants articular lesion and effectiveness of the treatment. For detection erosion bone process we used ultrasound, x-ray, MRI and diagnostic arthroscopy with synovial biopsy. The criteria of effectiveness of the therapy was achieving “inactive” arthritis and clinical pharmacologic remission (Carol A Wallace et al, 2004). We investigated (PCR-RFLP) the status of P53 gene this children with JIA and 100 healthy children living in Russian Federation.

Results Genotypes distributions of Arg72Pro and ins/del 16bp polymorphisms did not differ significantly (p>0,05) between JIA patients and controls. 69% girls with “active” persistence oligoarthirits within 3 years therapy (ACRpedi30-50) had genotype Arg/Pro, 20% girls genotype Pro/Pro and only 10% girls had normal genotype Arg/Arg (p<0,01). 80% girls achieved “inactive” oligoarthritis during a years of treatment had normal genotype Arg/Arg and only 20% genotype Arg/Pro (ACRpedi>70). In children with “active” polyarthirits within 5 years of treatment (ESR 30±12, ACRpedi 30-50) 79% girls had genotype Arg/Pro, but 66% boys had normal genotype Arg/Arg and only 34% genotype Arg/Pro. We didn’t find association between children oligo-polyarthritis JIA and intron polymorphism ins/del 16bp. We didn’t obtain differences of the genotype gene P53 in children with systemic JIA. All girls with enthesitis-related arthritis had genotype Arg/Pro + ins/del but the disease was less such aggressive (ACRpedi 70-90).

Conclusions Correlation between P53 gene genotypes and girls with JIA was shown for the first time. Girls with oligo-polyarticular variant of the disease with the mutant allele Pro have more aggressive form duration JIA compare children with homozygous Arg. Girls with homozygous genotype Arg/Arg have a less severe of articular lesions compare with girls who have the genotype Arg/Pro or Pro/Pro. The data obtained show that further studies are required to detect correlation between genotype P53 and juvenile idiopathic arthritis.

Disclosure of Interest None Declared