Inflammatory bowel disease consists of multifactorial diseases whose common manifestation is inflammation of the gastrointestinal tract and their pathogenesis remains unknown. This study aimed to analyse the gene polymorphisms in Brazilian patients with inflammatory bowel disease. A total of 101 patients diagnosed with inflammatory bowel disease were analysed for the tumour necrosis factor-alpha (-308 G/A; rs1800629) and interleukin-10 (-1082 G/A; rs1800896) gene polymorphisms. Genotyping was performed through polymerase chain reaction-sequence-specific primer, then fractionated on 2% agarose gel and visualized after staining by ethidium bromide. The anatomic-clinical form of Crohn's disease (CD) predominant was the inflammatory (32.75%), followed by fistulizing (29.31%) and 27.58% stricturing. As control group, a total of 136 healthy subjects, from the same geographical region, were enrolled. The statistical analyses were performed using R program. The frequency of the A allele at tumour necrosis factor-alpha was high in ulcerative colitis (UC) patients (51%) than in controls (22%; P > 0.01). No statistical difference was found with the genotypic and allelic frequencies of CD patients compared to controls (P = 0.54). The polymorphism -1082G/A of interleukin-10 was not statistical different between the diseases compared to controls. Tumour necrosis factor-alpha (TNF-α) (-308G/A) is associated with UC onset, suggesting that the presence of -308A allele could confer a relative risk of 3.62 more to develop UC in general population. Further studies, increasing the number of individuals, should be performed to ratify the role of TNF-α in the inflammatory bowel disease pathogenesis.

Background HLA-G may exert long-term immunotolerogenic effects through the generation of suppressor cells [reviewed in [1]]. Such features render HLA-G an attractive candidate gene for susceptibility to immune mediated diseases. Indeed, our group has observed a positive association of a 3’UTR haplotype encompassing the 14bp locus and the +3142C/G (rs1063320) and disease susceptibility in patients with systemic lupus erythematosus [2]. Objectives To investigate the genetic influence of the two HLA-G 3’UTR polymorphisms – the 14 bp insertion/deletion (rs1704) and the +3142C>G (rs1063320) – in the susceptibility to rheumatoid arthritis in a double-center study comprising a Southern-Brazilian cohort from Porto Alegre and Northern-Brazilian cohort from the city of Belém. Methods A total number of 546 RA patients and 531 controls was PCR genotyped for the two polymorphisms. Results Haplotype frequencies differed significantly between control groups from the Northern and Southern cohorts. After adjusting for city of origin and gender, we observed that female patients presented a higher frequency of the deletion-G (D/G) haplotype (OR=1.634, 95% CI=1.128–2.368, P=0.009). After stratifying for RF positivity, only the female RF+ group of patients presented statistical significance (OR=1.829, 95%C.I =1.243–2.690, P=0.002) - Table 1. Table 1.HLA-G D/G carrier frequencies in patients and comparison with controls AllFemalesMales N/Total (freq)N/Total (freq)N/Total (freq) Porto Alegre (South)  Controls0.206 (59/287)0.133 (16/120)a,b0.257 (43/167)  Patients (all)0.235 (80/340)0.242 (67/277)a0.206 (13/63)  RF+0.238 (67/281)0.247 (56/227)b0.204 (11/54)  RF–0.232 (13/56)0.234 (11/47)0.222 (2/9) Belém (North)  Controls0.338 (75/222)0.302 (38/126)c0.385 (37/96)  Patients (all)0.360 (71/197)0.374 (68/182)0.200 (3/15)  RF+0.405 (60/148)0.414 (58/140)c0.250 (2/8)  RF–0.242 (8/33)0.286 (8/28)0.0 (0/5) aP=0.015, bP=0.017, cP=0.072. Conclusions Our results suggest a differential influence of HLA-G 3’UTR polymorphisms in disease susceptibility, with the D/G haplotype as a risk factor for RA in RF+ females. References Carosella ED, HoWangYin K-Y, Favier B, LeMaoult J. Hla-g-dependent suppressor cells: Diverse by nature, function, and significance. Human immunology 2008;69:700-7. Consiglio CR, Veit TD, Monticielo OA, et al. Association of the hla-g gene +3142c>g polymorphism with systemic lupus erythematosus. Tissue Antigens 2011;77:540-5. Disclosure of Interest None Declared

Recently, progress has been achieved in the molecular understanding of the immune response in the onset of disease [3]. Several receptors of the extracellular interleukin (IL) and toll-like receptors families (TLR) have been implicated in IBD [4].