Association of Infl ammatory Bowel Disease and Tumor Necrosis Factor-863 C/A Polymorphism in Iraq

Abstract

Background: The underlying causes of infl ammatory bowel disease (IBD) are unknown, but they are thought to be a combination of genetics, environmental factors, abnormal immune responses, and disruption of the gut microbiota. This study aims to investigate the eff ect of tumor necrosis factor-alpha (TNF-α) -863 C/A(rs 1800630) single nucleotide polymorphism (SNP) in infl ammatory bowel patients and it is relation with the patient’s clinical characteristics. Methods: The study was conducted on 74 blood samples from patients of IBD including 47 patients with ulcerative colitis (UC) and 27 patients with Crohn’s disease (CD) in addition to 20 blood samples apparently healthy individuals, TNF-α-863 C>A genotype was screened by PCR and Sanger sequencing techniques. Results: The results showed that the homozygous CC genotype frequency was the higher genotype frequency in 45/60 (75%) for IBD patients with less than 50 years ages compared with 7/14 (50%) the IBD patients with more than 50 years, signifi cant high association OD (CI): 2.75 (1.38–4.08), The allelic C frequency in ulcerative colitis (UC) patients was (0.83) and signifi cantly higher than the A allele frequency (0.17) and it may act as risk factor infl ammatory disease. The homozygous CC genotype of the TNF-α-863 gene was 9/27 (70.37%) in CD patients compared with 6/20 (30%) in the control group with high signifi cant diff erences (p ≤ 0.01, OR=1.00). Signifi cant diff erences also applied for the heterozygous CA genotype in -863 SNP,it was 8/27 (29.62%) compared with the control group 14/20 (70%) the odds ratio (2.62), while the homozygous AA genotype frequency showed no signifi cant association with CD (p -1.00). Conclusion: The frequency of homozygous CC genotype of the TNF-α-863 gene was higer in CD patients than in the control group with signifi cant diff erences. Signifi cant diff erences also applied for the heterozygous CA genotype while the three genotypes (CC, CA and AA) of the TNF-α-863 gene showed non-signifi cant diff erences in ulcerative patients in comparison with the control.