Inflammatory bowel disease (IBD) is characterized by chronic inflammation of the gastrointestinal tract. IBD comprises primarily two disorders, which are Crohn's disease (CD) and ulcerative colitis (UC). These diseases are conditions with an imbalnced gut microbiome and the dysfunction of the immune system. Previous research shows that immunoglobulin G (IgG) and its glycosylation might have a role in the development and progression of IBD. MGAT3 gene encodes for the enzyme N-acetylglucosaminyltransferase III that catalyzes the addition of N-acetylglucosamine (GlcNAc) to the mannosyl core of glycans and produces a bisecting GlcNAc. The introduction of the bisecting GlcNAc results in the supression of further processing and elongation of N-glycans, since it can't be a suitable substrate for other glycosyltransferases. Genome-wide association studies (GWAS) have linked the MGAT3 gene with IBD. The aim of this research project is to analize CpG methylation in the MGAT3 gene from blood of people suffering from CD and UC, and to compare it the methylation of healthy people. Pyrosequencing following bisulfite conversion of DNA was done, and the stage of CpG methylation determined in five fragments od the MGAT3 gene. Results show a statistically significant change in CpG methylation in some of the fragments of the MGAT3 gene between patients with IBD and healthy people. This might indicate the potential of this gene of being a biomarker for these diseases.