Evaluation and Comparison of Aberrant Methylation Changes in Tlr4 Gene Promoter DNA Sequencing in Patients with Inflammatory Bowel Disease and Healthy Individuals

Background & Objective: According to the Iranian Ministry of Health prevalence of register‐identified inflammatory bowel disease among Iranian patients increased. The functional role of the TLR4 gene as a mediator of innate immune responses to pathogenic microbes in the gastrointestinal tract and its relationship to epigenetic changes is important. Our goal is to investigate the promoter DNA methylation of TLR4 gene in inflammatory bowel disease and to evaluate TLR4 gene as a biomarker to diagnose the disease. Materials & Methods: In this case-control study, DNA was extracted from peripheral blood of 55 volunteers including 35 patients with IBD and 20 healthy controls. High resolution melting technique (HRM) was used to investigate the promoter methylation changes of TLR4 DNA sequence in patients with inflammatory bowel disease and healthy controls. Results: According to the results of this study, methylation level analysis of CpG regions of TLR4 promoter showed no significant difference between 35 inflammatory bowel patients and 20 healthy individuals (P = 0.525). Also in this study, methylation changes were performed in relation to clinicopathological features that no significant relationship was observed. A significant assocation was observed between the levels of methylation in Fars compared to other ethnic groups such as Kurdish, Lor, Turk, Gilani, Arab, Mazandaran and Afghan (= 0.035 P Value). Conclusion: This study showed that there is no significant relationship between the level of promoter methylation of TLR4 gene in the blood of patients