Intercellular adhesion molecule 1 gene polymorphisms in inflammatory bowel disease

Intercellular adhesion molecule (ICAM)-1 is a single-chain cell surface glycoprotein that plays an important role in the recruitment of leukocytes at sites of inflammation and is up-regulated in intestinal mucosa of inflammatory bowel disease (IBD). ICAM-1 gene lies on chromosome 19p13, implicated in determining susceptibility to IBD. The human ICAM-1 gene contains two polymorphic sites in codon 241 (G241R) and 469 (K469E) which have been implicated in the susceptibility to a range of degenerative and inflammatory diseases. Recently, several reports have shown discordant data regarding the association of these polymorphisms with IBD. In particular, we found an association of IBD with the E/E genotype while allele E469 was associated with a subgroup of patients with more extensive location of Crohn's disease and penetrating behaviour. However, other studies reached different conclusions. A possible explanation for the discrepancy of results is probably the influence of the different geographic distribution of the genetic mutations.