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    Inflammatory Bowel Disease Health Center

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    Causes of Inflammatory Bowel Disease

    The cause of the inflammatory bowel diseases (IBD), ulcerative colitis, and Crohn's disease, is not known. Studies suggest they are caused by a combination of things, including genes, environmental factors, and problems with the immune system.

    There is strong evidence to suggest a genetic basis for IBD, including:

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    7 Things People With IBD Wish You Knew

    No one diagnosed with Crohn’s disease or ulcerative colitis understands everything about their condition. Scientists and doctors don’t. Researchers have spent millions trying to figure it out. So when someone doesn’t know what IBD is all about -- that those letters stand for inflammatory bowel disease, or that it's an umbrella term for Crohn’s and ulcerative colitis -- we shouldn’t be surprised. These diseases are complicated. They look different with every person. And they’re often uncomfortable...

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    • Family history: As many as 20% of people with IBD have a family history of it.
    • Race and ethnicity: IBD is more common in white people. It's also more common in Jews, especially Ashkenazi Jews.

    Inflammatory Bowel Disease Genes

    In 2006, the first gene associated with Crohn's disease, the NOD2 gene, was identified. Since then, researchers have uncovered over 200 related genomic regions for IBD.

    Finding a genetic link would help scientists understand the changes that lead to IBD, and help them improve treatments. A genetic link could also lead to a test for IBD.

    WebMD Medical Reference

    Reviewed by Melinda Ratini, DO, MS on April 13, 2015

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