Receptor for Advanced Glycation End Products (RAGE) Polymorphisms In Inflammatory Bowel Disease

Overview

The inflammatory bowel diseases (IBD) are chronic inflammatory disorders of the gastrointestinal tract that manifests as Crohn's disease (CD) and Ulcerative colitis (UC . Over the last two decades the incidence pattern of UC showed significant increase in previously low incidence areas such as Asia and the Middle East. In addition to microbial and environmental factors influencing IBDs, they are complex genetically, where hundreds of genetic loci contribute to disease susceptibility . Genome-wide association studies (GWAS) have identified several genetic susceptibility loci for UC and CD. Among the genetic factors involved, there are several single nucleotide polymorphisms (SNP) in molecules of the immune system associated with either susceptibility or protective effects to IBD progression, but with contradictory associations, mainly depending on the onset (adult or pediatric), sample size differences, inadequate statistical power and on the ethnicity-dependent genetic background. Growing evidence indicates that (RAGE) is involved in chronic inflammation and cancer. It is a transmembrane receptor normally expressed at low levels on a wide range of cells, bind a broad spectrum of ligands. Activated RAGE induces the synthesis of proinflammatory molecules resulting in magnifying rather than dampening inflammation . The human RAGE gene is located on chromosome 6p21.3, in the so-called class III of the major histocompatibility complex. The SNP at the -374A/T and -429T/C of the promoter region have been shown to increase protein synthesis threefold and twofold, respectively. Few studies found that RAGE is up-regulated in IBD, and it appears to play a role in the mechanisms involved in chronic inflammation Little information is available on the possible association of such polymorphisms with IBD. Few studies was carried out in different countries to assess these polymorphisms in IBD, resulting in conflicting results, between supporting and denial of the association. Due to this discrepancy we aimed to study this gene in our community including IBD patients.

This study aims: 1. To investigate the association of both allelic and genotypic -374T/A and -429T/C polymorphisms and inflammatory bowel disease. 2. To correlate the relation between the studied SNPs , disease activity and the clinical features of the disease. Subjects and Methods: This is a case control study. The study will include 90 patients diagnosed as IBD. Patients will be recruited from outpatient department of Elraghey Liver Hospital in Assiut University Hospital.The clinical disease activity was calculated using the Montreal classification of disease activity and Crohn's Disease Activity Index (CDAI) for UC and CD patients, respectively (Silverberg et al., 2005). -Also, 90 apparently healthy subjects (age and sex matched with the patient group) will be included as control group.