Interleukin-1 single-nucleotide polymorphisms as risk factors for susceptibility of inflammatory bowel disease: an Iraqi Arab population-based study

ABSTRACT Objectives: It is aimed to determine the association between four single-nucleotide polymorphisms (SNPs) of IL1 genes (rs1800587: IL1A？889 C/T, rs16944: IL1B？511 T/C, rs2234650: IL1R1pst1 1970 T/C and rs315952: IL1RAmspa1 11100 T/C) and the two types of IBD (UC and CD) in samples of Iraqi Arab patients. Materials and Methods: Hundred Iraqi patients (66 UC and 34 CD) were genotyped for these SNPs by polymerase chain reaction-specific sequence primer (PCR-SSP) assay. Results: A significant increased frequency of IL1A？889 C allele was observed in total IBD patients compared to controls (72.0 vs. 56.5%; Odds ratio = 1.98; Corrected p = 0.001). For IL1B？511 and IL1R1pstl 1970 SNPs, the T allele frequency was significantly increased in total patients (62.0 vs. 49.1%; Odds ratio = 1.69; Corrected p = 0.02 and 65.0 vs. 46.7%; Odds ratio = 2.12; Corrected p = 1 × 10？4, respectively). Allele and genotype frequencies of IL1RAmspa 11100 SNP showed no significant variation between total patients and controls. A similar profile of was observed in UC patients, but IL1RAmspa 11100 T allele frequency was significantly increased in patients (72.7 vs. 60.2%; Odds ratio = 1.76; Corrected p = 0.05). Among CD patients, IL1A？889, IL1R1pstl 1970 and IL1RAmspa 11100 SNP allele frequencies shared their distribution in total IBD patients. For IL1B？511 SNP, allele and genotype frequencies showed no significant difference between CD patients and controls. Conclusion: These data suggests a significant role of IL1 SNPs in etiopathogenesis of IBD in Iraqi Arab population