BackgroundDespite the recent progress in our understanding of the genetic predisposition to systemic lupus erythematosus (SLE) its clinical and functional significance is not fully clarified yet and needs to be implemented in personalized care [1].ObjectivesTo estimate the association between some single nucleotide polymorphisms (SNPs) of 9 non-HLA genes-candidates as STAT4 rs7574865, PTPN2 rs2542151, PTPN22 rs2476601, AGER rs1035798, TRAF1/C5 rs3761847, SLC7A11 rs13128867, RUNX1 rs9979383, IL6 rs1800795, IL6R rs2228145, IL6R rs4845618 and susceptibility to SLE in Belarusian women for the following predictive model development.MethodsWe examined 316 women: among them 59 SLE patients (mean age 39.84, CI95% 36.62-43.06) classified according to the 1997 American College of Rheumatology (ACR) revised classification criteria and 257 age-matched healthy controls (blood donors, mean age 38.12, 95% confidence interval (CI95%) 36.77-39.46). Deoxyribonucleic acid was extracted from peripheral blood samples by phenol-chloroform method. Genotyping was performed by real-time PCR with fluorescent probes. Descriptive analysis, test for Hardy–Weinberg equilibrium, multiple inheritance models (co-dominant, dominant, recessive, over-dominant and log-additive) for single SNPs, Akaike information criteria (AIC) and Bayesian information criteria (BIC) were analyzed using SNPStats web tool [2]. Pearson χ 2 (χ 2), two-way Fisher exact test (F, p 2-t), odds ratio (OR), likelihood ratio of positive (LR +) and negative (LR –) tests with corresponding CI95% were also calculated.ResultsExact test for all genotype frequencies distribution of all studied SNPs didn’t reveal significant differences with Hardy-Weinberg equilibrium in all controls and SLE groups. We noted significant increase of minor ТТ genotype frequency of STAT4 rs7574865 in SLE vs healthy women with recessive inheritance model as the best-fitting one according to its less AIC and BIC values (OR=3.78 (CI95% 1.35-10.62); p=0.016; LR + =3.45 (CI95% 1.37-8.60); LR – =0.91 (CI95% 0.84-0.98)). We revealed protection of minor A allele of AGER rs1035798 carriership with log-additive model of inheritance as the best-fitting one according to AIC and BIC values against SLE development in women (OR=0.52 (CI95% 0.33-0.83); p=0.004; LR + =0.70 (CI95% 0.50-0.93); LR – =1.47 (CI95% 1.10-1.86)). We also noted significant increase of minor allele G frequency of TRAF1/C5 rs3761847 in SLE vs healthy women with dominant inheritance model (OR=3.61 (CI95% 1.05-12.38); p=0.019; LR + =1.30 (CI95% 1.03-1.43); LR – =0.36 (CI95% 0.12-0.92)) and increase of AA genotype frequency in healthy women (p 2-t =0.041). We revealed that minor allele G of PTPN2 rs2542151 is more frequent in SLE women vs healthy controls and has overdominant model of inheritance (OR=1.98 (CI95% 1.09-3.59); p=0.026; LR + =1.57 (CI95% 1.07-2.20); LR – =0.79 (CI95% 0.62-0.97)).There were no significant differences in genotypes and alleles distribution for PTPN22 rs2476601, RUNX1 rs9979383, SLC7A11 rs13128867 and IL6 rs1800795 in studied population and we noted only non-significant tendency in minor SNP genotypes distribution of IL6R rs4845618 and IL6R rs2228145 between healthy controls and women with SLE.ConclusionOur data suggest the susceptibility to SLE in women with ТТ genotype of STAT4 rs7574865 polymorphism and allele G carriers of both TRAF1/C5 rs3761847 and PTPN2 rs2542151 as well as protective role of AGER rs1035798 A allele carriership againt SLE development in women of Belarusian population.References[1]Ghodke-Puranik Y, Niewold TB. Immunogenetics of systemic lupus erythematosus: A comprehensive review. J Autoimmun. 2015;64:125-36.[2]Solé X, Guinó E, Valls J, Iniesta R, Moreno V. SNPStats: a web tool for the analysis of association studies. Bioinformatics 2006;22(15):1928–29.AcknowledgementsThis research was supported by The Research Technical Program “DNA Identification” (2017–2021), project number: 6.4Disclosure of InterestsNone declared

BackgroundRheumatoid arthritis (RA) is a chronic inflammatory disease characterized by autoimmune inflammatory response focused in the synovium. RA is a complex disorder with significant genetic component and it is also known to have possible environmental triggers. Microbiota and bacterial infections play a significant role in RA etiology. The onset of RA may be accompanied by the previous or ongoing chlamydia infection in some cases.Objectivesto determine genetic variants of susceptibility to RA in Belarusian populationMethods650 individuals were divided into 2 cohorts: 305 patients with RA (59.69 ± 12.20), and 345 controls (mean age 37.42 ± 10.62). Patients with RA were further stratified into two subsets – those with catamnestic Chlamydia trachomatis/Chlamydophila pneumoniae infection (43, “RAChl+”) and those without (262, “RAChl-“). 11 SNPs of 10 genes (IL6 (rs1800795), IL6R (rs2228145 and rs4845618), STAT4 (rs7574865), TRAF1/C5 (rs3761847), RUNX1 (rs9979383), RUNX3 (rs11249215), PTPN2 (rs2542151), PTPN22 (rs2476601), AGER (rs1035798), SLC7A11 (rs13128867)) were genotyped using Real-time PCR or PCR-RFLP.ResultsIt was found that homozygous TT genotype at the rs7574865 locus of the STAT4 gene and CT+TT genotypes at the rs2476601 locus of the PTPN22 gene are associated with RA in general (OR 2.71 [1.31 – 5.61]; p = 0.005 and OR 2.47 [1.75-3.48] p<0.000, respectively). CC genotype at the rs9979383 locus of the RUNX1 gene and AG+GG genotypes at the rs11249215 locus of the RUNX3 gene revealed protective effect (OR 0.63 [0.40-0.98] p=0.036 and OR 0.58 [0.36-0.92] p=0.02, respectively). The lack of association with RA was shown for polymorphic loci of the IL6 (rs1800795), IL6R (rs2228145 and rs4l45618), SLC7A11 (rs13128867), AGER (rs1035798), PTPN2 (rs2542151) and TRAF1/C5 (rs3761847) genes. For RA subsets stratified according to presence/absence of the C. trachomatis/C. pneumoniae infection it was shown that CC genotype at the rs1800795 locus of the IL6 gene and AA genotype at the rs11249215 locus of the RUNX3 gene were associated specifically with the risk of developing Chlamydia infection-associated RA (OR 5.22 [1.85–14.71] p=0.0024 and 2.63 [1.09-6.35] p=0.037). In addition, TG+GG genotypes at the rs2542151 locus of the PTPN2 gene is also associated with RAChl+ clinical phenotype (2.10 [1.10-3.99] p=0.025). No association with either of disease subtypes was revealed for polymorphic loci RUNX1 (rs9979383), IL6R (rs2228145, rs4845618), AGER (rs1035798), SLC7A11 (rs13128867), TRAF1/C5 (rs3761847).ConclusionThus, the polymorphic variants of STAT4, a key gene of autoimmunity, and PTPN22 gene, that is involved in the JAK/STAT pathway of immune response, increase the RA susceptibility in general cohort for the Belarusian population. At the same time, CC genotype at the rs1800795 of the IL6 gene, its product being central proinflammatory cytokine, and AA at the rs11249215 locus of the RUNX3 gene, that is involved in T-cell initiated immune response, as well as the genotypes TG+GG at the rs2542151 locus of the PTPN2 gene, involved in signaling pathways of immune response through T-cell activation, are associated only with RAChl+ clinical phenotype. Our data may indicate that genetic variants of STAT4 and PTPN22 contribute to genetic basis of the pathogenesis of RA through renewal of T-cell initiated immune response.AcknowledgementsThis research was supported by The Research Technical Program “DNA Identification” (2017–2021), project number: 6.4Disclosure of InterestsNone declared

Background:Systemic lupus erythematosus (SLE) has a significant genetic predisposition. Many genetic variants of susceptibility to SLE have been published and analyzed, but the clinical and functional significance of the various genotypes has not yet been clearly defined [1].Objectives:To estimate the association between some of non-HLA gene polymorphisms such as STAT4 rs7574865, RUNX1 rs9979383, IL6 rs1800795, IL6R rs2228145, IL6R rs4845618 and susceptibility to SLE in Belarusian population as well as some disease manifestations.Methods:We examined 383 healthy blood donors and 54 SLE patients (18-72 years old, median age 35) classified according to the 1997 American College of Rheumatology (ACR) revised classification criteria [2]. Deoxyribonucleic acid was extracted from peripheral blood samples by phenol-chloroform method. Genotyping was performed by real-time PCR with fluorescent probes. Differences of distribution of all the single nucleotide polymorphism (SNP) genotypes and their associations with secondary antiphospholipid syndrom (APS) and lupus arthritis were analyzed using Pearson χ2 (χ2) and two-way Fisher exact test (F, p2-t). Diagnostic odds ratio (dOR), likelihood ratio of positive (LR +) and negative (LR –) tests and corresponding 95% confidence intervals (CI) were also calculated.Results:We revealed significant difference in STAT4 rs7574865 genotypes in SLE patients and healthy donors (χ2=8,27, р=0,016) with significant increase of ТТ genotype frequency in SLE patients vs healthy donors (χ2=6.83 p=0.009; p2-t =0.020; dOR=3.78 (CI95% 1.36-10.55); LR+ =3.44 (CI95% 1.35-8.71); LR– =0.91 (CI95% 0.83-0.98)). Lupus arthritis was more common in risk TT-genotype SLE carriers than in other SLE patients (χ2=5.902 p=0.015; p2-t =0.027).We revealed significant increase of СТ genotype (RUNX1 rs9979383) in healthy donors vs SLE patients (χ2=4.14; p=0.042; dOR=0.53 (CI95% 0.29-0.98); LR+ =0.69 (CI95% 0.45-0.99); LR– =1.3 (CI95% 1.01-1,56)). Lupus arthritis was more common in SLE СТ-genotype carriers than in other SLE patients (χ2=4.66 p=0.031; p2-t =0.058).Significant differences in IL6 rs1800795, IL6R rs2228145 and IL6R rs4845618 genotypes distribution between studied groups were not found (χ2, p=0.427, p=0.559 and p=0.407, correspondingly) but GG-genotype (IL6 rs1800795) carriership in SLE patients was associated with increased APS frequency (χ2=4.45, p=0.035; dOR=0.19 (CI95% 0.04-0.9); LR+ =0.28 (CI95% 0.07-0.93); LR– =1.41 (CI95% 1.03-1.64).Conclusion:Our data suggest the susceptibility to SLE in ТТ genotype of STAT4 rs7574865 polymorphism, protective role of СТ genotype of RUNX1 rs9979383 for SLE and association between GG-genotype of IL6 rs1800795 and APS in SLE patients in Belarusian population. Lupus arthritis was associated with ТТ genotype of STAT4 rs7574865 and СТ genotype of RUNX1 rs9979383.References:[1]Chen L, Morris DL, Vyse TJ. Genetic advances in systemic lupus erythematosus: an update. Curr Opin Rheumatol 2017;29:423–33.[2]Hochberg MC. Updating the American College of Rheumatology Revised Criteria for the classification of Systemic Lupus Erythematosus. Arthritis Rheum 1997;40:1725.Disclosure of Interests:None declared

Background:Rheumatoid arthritis (RA) is a chronic systemic disorder of the connective tissue of still unknown aetiology and complex autoimmune pathogenesis that primarily affects small joints. HLA alleles provide for 11-37% of the RA heritability, suggesting the substantial role of the non-HLA loci in genetic predisposition to RA. Among non-HLA loci,IL6, IL6RandSTAT4genes attract attention, however, the data concerning their influence on RA risk are somewhat contradictory.Objectives:The aim of the study was to analyze the involvement of four SNPs (STAT4rs7574865,IL6rs1800795,IL6Rrs2228145 and rs4845618) in RA susceptibility.Methods:187 patients diagnosed with RA (mean age 58.2 ± 11.9), and 380 healthy blood donors (mean age 37.18 ± 10.69 years) were included into the study. DNA extraction from peripheral blood samples was performed using the phenol-chloroform method. SNPs were genotyped using the real-time PCR with fluorescent probes. The allele and genotype frequencies were compared using the χ2 test. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using the VassarStats online tool.Results:Utilizing recessive genetic model we found an association between TT genotype ofSTAT4rs7574865 (OR = 2.362; 95%CI [1.0378 – 5.376], p = 0.038) and RA. ForIL6rs1800795, it was found that CC genotype had significantly higher frequency among patients with rheumatoid arthritis as compared to that in controls (OR = 1.52; 95%CI [1.02 – 2.27], p = 0.0456). No associations ofIL6Rrs2228145 and rs4845618 SNPs with risk of RA were found in the total group of patients vs. controls. It was also shown thatIL6rs1800795 CC genotype frequency was significantly higher among the patients with RF-negative status (p = 0.0019).Conclusion:Thus, we provide evidence for association of theSTAT4rs7574865 andIL6rs1800795 variants with risk of RA in the Belarusian population, some features of interplay being revealed between gene polymorphisms analyzed and RA antibody status. Abovementioned SNPs may contribute to RA genetic susceptibility in the Belarusian population.Disclosure of Interests:None declared

Background and Aims Glomerular diseases (GD) often have genetic predisposition, especially those autoimmune or immune complex-mediated. Our aim was to assess an impact of genetic polymorphism in STAT4 rs7574865 and rs3821236, VEGF rs699947 and PTPN22 rs2476601 on the risk of development of primary (PG) and secondary (SG) glomerulopathies in children. Method We enrolled 81 child with GD (m:f 33/48) and 335 healthy controls (m:f 184/151). Patients of the study group were arranged into two groups: 1st - with PG (38 children aged 3-17 yrs, 13±3,45, m:f 22/16) and 2nd - with SG (43 children aged 7-17 yrs, 13±3,59, m:f 11/32). 1st group included 35 patients with hereditary nephritis, 2 with IgA nephropathy, 1 – FSGS. 2nd group included 10 patients with ANCA associated vasculitis, 11 with IgA vasculitis, 22 with systemic lupus erythematosus (SLE). These patients were identified and monitored at the National Center for Pediatric Nephrology. Control group (CG) was matched with the study groups for age and sex and included 335 healthy children (m:f 184/151, age 2-17 yrs, 14,28±2,56). We analyzed DNA by polymerase chain reaction for identification of genotypes. Results The frequency of genotypes and allels for STAT4 rs 7574865 was found to be GG 55,26% in 1st, 46,51% in 2nd versus (vs) 62,09% in CG; GT 39,47%, 41,86% vs 32,24%; TT 5,26%, 11,63% vs 5,67%; for minor allele T 25,00%, 32,60% vs 21,79%, respectively. For STAT4 rs3821236: GG found in 65,79% in 1st, 55,81% in 2nd vs 65,07% in CG; GA genotype in 26,32%, 41,86% and 30,15%; AA genotype in 7,89%, 2,33% and 4,78%; minor allele A in 21,05%, 23,26% and 19,85%, respectively. For VEGF2578 rs 699947: AA 28,95% in 1st, 30,23% in 2nd vs 20,30% in CG; AC 44,74% and 51,16% vs 57,31%; CC 26,32% and 18,60% vs 22,39%; minor allele C 48,68%, 44,19% vs 51,04% in 1st and 2nd vs CG, respectively. For PTPN22: CC 68,42% in 1st, 59,46% in 2nd vs 72,95% in CG; CT 28,95%, 35,14%, 24,59%; TT 2,63%, 5,41% and 2,46%; minor allele T in 17,11%, 22,97% vs 14,75% in 1st,2nd and CG, respectively. The distribution of genotypes observed was tested with the Hardy-Weinberg Equilibrium. There were no differences found in rates of polymorphic genotypes in CG and patients with GD. For PTPN22 rs 2476601 and VEGF2578 rs6999467 no statistically significant difference between children of 1st, 2nd and CG was observed. We found the difference between patients with GD and healthy children (HC) for minor allele T of STAT4 rs7574865 (OR [95%CI]=1,73 [1,06-2,82], p=0,03), which was most prominent for female patients with SG (OR [95%CI]=2,31 [1,3-4,12], p=0,005). The development of SG was associated with the presence of GT+TT genotype (vs GG genotype) of STAT4 rs7574865 (OR=4,92; 95% CI [2,62-9,23]; p&lt;0,001). Statistical testing showed significant differences between healthy female controls and SLE females for minor allele T of STAT4 rs7574865 (OR [95%CI]=2,14 [1,07-4,27], p=0,04) and GT+TT genotypes vs GG genotype of STAT4 rs7574865 (OR=2,54; 95%CI[1,00-6,42]; p&lt;0,05). The analysis of genotypes/alleles for polymorphic locus rs3821236 of STAT4 revealed significant association of GA genotype (OR[95%CI]=2,55 [1,17-5,55], p=0,021), as well as of the sum of genotypes with at least one minor allele (GA+AA) (OR[95%CI]=3,51 [1,59-7,76], p=0,002) with the development of SG in girls. An association of the presence of the minor allele A of STAT4 rs3822136 with the likelihood of SG development in females was observed (OR[95%CI]=2,69 [1,5-4,83], p=0,001). Conclusion Minor allele T and GT+TT genotypes of STAT4 rs7574865 is associated with the risk of SG development in children and especially with the risk of SLE development in girls. Minor allele A and GA+AA genotypes of the STAT4 rs3822136 are associated with the predisposition to SG in girls. Minor allele T and GT+TT genotypes of the PTPN22 rs 2476601 are observed to be more frequent in both groups of GD and especially in girls, though failed to be statistically significant (p&gt;0,05).