THU0328 Mir-499 polymorphism is associated with susceptibility to psoriatic arthritis – preliminary study

Abstract

Background Polymorphism within the miR-499 has been reported to be associated with susceptibility to rheumatoid arthritis (RA) in various populations. Objectives Our study aimed to find out whether similar association could be observed also in Polish population in both RA and psoriatic arthritis (PsA) patients. Methods For this purpose 359 individuals were studied, including 111 RA patients, 86 patients with PsA and 162 healthy blood donors that served as a control group.Genotyping for miR-499 rs3746444 T/C was performed using a LightSNiP assay. Results Distribution of the miRNA-499 alleles and genotypes was similar in RA patients and controls. Among RA patients those carrying the CC homozygous genotype presented with lower DAS28 at diagnosis (0.027) but higher CRP levels after 12 weeks of anti-TNF treatment (p=0.042).Interestingly, the TT genotype (rs3746444) was overexpressed in patients with PsA as compared to controls (OR=1.85, p=0.034) but its frequency was not significantly different when compared to RA cases. This polymorphism was also not found to be associated with clinical parameters in PsA patients. Conclusions These results show that miR-499 rs3746444 T/C polymorphism may constitute a risk factor for psoriatic arthritis development. Acknowledgements This work was supported by the NCN 2016/21/B/NZ5/01901 project. Disclosure of Interest None declared