Keynote Message

Granulomatous colitis (GC) is a severe inflammatory bowel disease (IBD), typically diagnosed in boxer dogs and French bulldogs, but also other mastiff breeds, younger than four years of age. Affected dogs have diarrhea that leads to chronic weight loss, anemia, and debilitation. Previous studies have identified invasive bacteria within immune system cells, macrophages, in the colons of diseased dogs. Antibiotic treatments usually yield clinical improvement; however, antibiotic-resistant bacteria are present in some cases and persistently affected dogs suffer greatly. Elimination of this disease would be greatly facilitated by a genetic screening test to identify carriers. Identifying the genetic basis of GC could also provide comparative insights to inform the diagnosis and treatment of people with CD/IBD. Using a GWAS approach we have identified a region of DNA on chromosome 38 that is strongly associated with GC. It contains multiple genes that are known to impact the killing of E.coli bacteria and inflammatory responses. To identify the specific gene or genes that are affected, we are analyzing DNA sequences and expression patterns of these genes in dogs with GC and controls.

Key References

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