THURSDAY, March 8, 2012 (HealthDay News) -- Researchers have identified five new genetic mutations associated with Crohn's disease in Jews of Eastern European descent (Ashkenazi Jews) and say their findings may help explain why Crohn's is nearly four times more prevalent in this group than in the general population.
Crohn's is an inflammatory bowel disease that causes swelling and irritation in the digestive tract. Symptoms include abdominal pain, diarrhea, rectal bleeding, weight loss, and fever.
Previous research pinpointed 71 genetic variants associated with Crohn's disease risk in people of European ancestry. In this new study, Mount Sinai School of Medicine researchers compared almost 2,000 Ashkenazi Jews with Crohn's disease to another 4,500 Ashkenazi Jews without the disease.
The team found 12 of the known risk variants and also discovered five new genetic risk regions on chromosomes 5q21.1, 2p15, 8q21.11, 10q26.3 and 11q12.1.
"This is the largest study to date, and the first to discover the unique risk factors of Crohn's disease in the Ashkenazi Jewish population," study leader Inga Peter, an associate professor of genetics and genomic sciences, said in a Mount Sinai news release.
"The prevalence of this disease is so much higher in Ashkenazi Jews, and the involvement of genetic variants predominant in this population might help understand why that is," she added.
The researchers also found that the genetic structure of the newly-identified regions associated with Crohn's disease risk in Ashkenazi Jews was much less diverse than that of non-Jewish Europeans.
"Not only did we discover different risk factors for Ashkenazi Jews, but we found that some previously known risk factors are more potent to this population," Peter said. "Armed with this new information, we can begin to analyze the specific signals in order to pinpoint causal genetic mutations, discover why they are malfunctioning, and eventually develop novel treatment approaches."
The study is published March 8 in the online edition of PLoS Genetics.
The U.S. National Institute of Diabetes and Digestive and Kidney Diseases has more about Crohn's disease.