CHOP Research
More Crohn's Disease Genes Discovered by CHOP Researchers (from Childrens Hospital of Philadelphia website)
Researchers at The Children’s Hospital of Philadelphia contributed important pediatric data to the largest-ever genetic study of Crohn’s disease. In this study, the International IBD Genetic Consortium drew on samples from more than 22,000 patients and 29,000 controls from around the world.
About inflammatory bowel disease
A chronic, painful inflammation of the digestive tract, inflammatory bowel disease (IBD) includes Crohn’s disease (affecting any part of the digestive tract) and ulcerative colitis (limited to the large intestine). It affects some 2 million U.S. children and adults.
An abnormal overreaction in the body’s immune system is believed to trigger the inflammation in IBD. Like many common disorders, IBD has complex causes, resulting from any of a number of genes that may interact with each other and with environmental factors.
About the study
Hakon Hakonarson, MD, PhD, director of the Center for Applied Genomics; Kai Wang, PhD, also from that Center; and Robert N. Baldassano, MD, director of the Center for Pediatric Inflammatory Bowel Disease, were co-authors of the current paper, and have collaborated previously with each other on genetic studies of pediatric IBD. The current study appeared online Nov. 21, 2010 in Nature; the study leader was Miles Parkes from the University of Cambridge in the UK.
Study findings
The international study consortium identified 30 new locations at which gene variants were associated with a higher risk of having Crohn’s disease. When added to previous studies, a total of 71 gene variants have now been discovered, and the total is expected to grow in the future. Currently, more genes have been linked to Crohn’s disease than to any other disease.
Because the gene variants found in this study are believed not to directly cause IBD, but instead act as signposts to other gene variants more directly involved in causation, further studies are needed to identify causative genes and understand their biological functions. However, many of the candidate genes affect signaling within the immune system and regulate immune responses. Many of the gene locations found in the current study have previously been linked to other autoimmune diseases such as asthma, celiac diseases, type 1 diabetes and rheumatoid arthritis.
Genetics play a larger role in children with IBD