New genes for Crohn's disease found
Crohn's disease genes
Just a few months after their landmark article in Science magazine reporting the discovery of strong links between variations in a gene that codes for a cellular receptor involved in controlling inflammation and Crohn's disease, a consortium of U.S. and Canadian researchers is reporting in today's online issue of Nature Genetics that they have discovered several more genetic variations that are strongly linked to an increased risk for the disease.
The discovery of these Crohn's disease-associated genetic variants has identified several key biological pathways that will be the focus of further research to understand how the debilitating inflammatory process is initiated and maintained in many cases of the disease.
"As we collect more and more data from these genome-wide association studies, we continue to discover susceptibility genes for Crohn's and other inflammatory bowel diseases (IBDs). More importantly, those genes are leading us to the biological pathways that relate to IBD pathogenesis. By understanding these pathways, we may be better able to develop more effective therapies for IBD," said consortium member Richard H. Duerr, M.D., associate professor of medicine and human genetics at the University of Pittsburgh, co-director of the Inflammatory Bowel Disease Center and director of the IBD Genetics Program.
These latest results are helping to fill in the gaps in knowledge about Crohn's and other IBDs, which affect more than 1 million Americans. Because IBDs tends to run in families and are more frequent in certain ethnic populations, especially Ashkenazi Jews, scientists have long suspected that they have a significant genetic component.
Previous genetic studies have found strong links between Crohn's disease and mutations in two genes, one known as CARD15, and, more recently, a gene known as IL23R, which codes for the immune cell receptor for interleukin-23, an important biochemical mediator of inflammation in the body.
However, mutations in these two genes alone cannot account for the entire genetic component of the disease. To identify additional genes that are associated with Crohn's, the researchers scanned more than 300,000 single nucleotide polymorphisms, or SNPs, in the genomes