Scientists have discovered a new gene that may predispose humans to Crohn's disease. Researchers from the University Hospital of the Christian-Albrechts University in Kiel, Germany and Applied Biosystems identified and characterized a novel genetic variation in a gene not previously associated with the disorder that provides further evidence that an abnormal immune response to bacteria in the digestive tract may lead to the intestinal inflammation characteristic of the disease.
The results of the team's three-year collaboration will be published in the February issue of Nature Genetics.
"With further evidence that genetic factors may be compromising the defenses of the intestinal barrier in Crohn's disease,” says Francisco De La Vega, Ph.D., scientific fellow, Applied Biosystems and a co-author of the paper, “we believe pharmaceutical researchers have an opportunity to design new therapies that may address the root cause, not just the symptoms, of this chronic disease.”
The research team tested DNA samples from patients with Crohn's disease using Applied Biosystems’ SNPlex™ Genotyping System. The team conducted a genome-wide association scan of approximately 20,000 coding genetic variants that are thought to produce functional changes at the protein level.
Among their findings, the researchers identified a protein-coding SNP in the autophagy-related 16-like (ATG16L1) gene. Neither the ATG16L1 gene, nor this specific genetic variation, has been previously implicated in Crohn's disease. The ATGI6LI gene is part of the autophagosome biological pathway, which normal cells use to destroy harmful bacteria.
"With the discovery of APG16L1 as a new gene associated with Crohn's disease,” says Stefan Schreiber, M.D., Ph.D., professor of medicine at the Christian-Albrechts University in Kiel, Germany, and senior author of the study, “we have discovered a further piece of evidence that highlights epithelial cells in the digestive tract and therefore a weakened barrier function as the most likely target for the underlying etiology of chronic inflammatory bowel disease."