A new study has found that that celiac disease and Crohn's disease, both inflammatory diseases of the gastrointestinal tract, share some common genetic links.
An international team of researchers conducted the study, which may help explain why people who have celiac disease appear to have a higher rate of Crohn’s disease than the general population. The data may also lead to new treatments that address the underlying inflammation involved in both conditions.
The causes of the diseases are only partly understood, although it is known that genetic and environmental factors are involved. At least one in every 100 individuals in the Western world develop celiac disease; Crohn's disease is much less common but can be accompanied by more severe symptoms as it can affect the whole gastrointestinal tract.
Celiac patients develop an inflammation of the small bowel in reaction to gluten, a protein that’s found in wheat and other grains like rye and barley. The primary 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 cause of these diseases, and to provide patients better treatments, knowledge of the genetic background of the diseases is vital.
This study combined the results from genetic investigations into both diseases to show that part of the genetic background of Crohn's disease and celiac disease is shared, which confirms a common pathogenesis for these disorders.
Although additional studies will be necessary to understand the mechanisms by which these variants influence both Crohn's disease and celiac disease, the researchers believe the current study provides proof that risk factors shared across related diseases can be identified by directly combining genetic data from clinically distinct diseases.
The analysis was published in the January 2011 Issue of PLoS Genetics, and identified two new shared risk loci and two shared risk loci that had previously been independently identified for each disease.
Resource: PLoS Genetics, January 2011 - A Meta-Analysis of Genome-Wide Association Scans Identifies IL18RAP, PTPN2, TAGAP, and PUS10 As Shared Risk Loci for Crohn's Disease and Celiac Disease