January 28, 2011

Celiac and Crohn’s: Similar Diseases?

(Ivanhoe Newswire) -- A recent study has shown that celiac disease and Crohn's disease, both inflammatory diseases of the gastrointestinal tract, share at least four genetic risk loci.

Researchers from the University of Groningen, The Netherlands; the Broad Institute, USA; and the Universit© de Montr©al and Montreal Heart Institute in Canada collectively performed a pooled meta-analysis of genome-wide data for celiac disease and Crohn's disease. This meta-analysis has furthermore identified two new shared risk loci and two shared risk loci that had once been autonomously identified for each disease.

The pathogenesis of both celiac disease and Crohn's disease is still moderately understood, though it is recognized that they are affected by both genetic and environmental risk factors. At least one in every hundred individuals in the Western world develops celiac disease; however, Crohn's disease is much less common but can be accompanied by harsher symptoms as it can affect the entire gastrointestinal tract. Celiac patients develop an inflammation of the small bowel in reaction to gluten, whereas there is no particular known autoantigen for Crohn's disease. Conversely, the chief cause of Crohn's disease is thought to be a dysregulated immune response to gut bacteria. In order to gain a better understanding of the pathogenesis and to aid in developing therapies against these disorders, knowledge and understanding of the genetic background of the diseases is essential.

As it has earlier been revealed that celiac patients are at an elevated risk of developing Crohn's disease than non-sufferers, it had been thought that the two illnesses would share genetic risk loci. This study ultimately combined the results from the genetic investigations into both diseases to illustrate that part of the genetic background of Crohn's disease and celiac disease is shared, which confirms a universal pathogenesis for these disorders.

Although further studies are needed to identify the mechanisms by which these variants influence both Crohn's disease and celiac, the present study provides evidence of principle that risk factors shared across related diseases can be identified by exactly combining genetic data from clinically distinct diseases.

SOURCE: PLoS (Public Library of Science), 27 January 2011