5 Genetic Regions Tied to Irritable Bowel

(WebMD)  Five newly identified genetic regions may help explain how childhood inflammatory bowel disease (IBD) develops.

A new study shows at least one of the five new gene regions associated with childhood IBD is directly involved in the biological process that causes the painful inflammation of the digestive tract associated with the disease.

"This is an evolving story of discovering what genes tell us about the disease," says researcher Robert N. Baldassano, MD, director of the Center for Pediatric Inflammatory Bowel Disease at Children's Hospital, in a news release. "Pinpointing how specific genes act on biological pathways provides a basis for ultimately personalizing medicine to an individual's genetic profile."

Inflammatory bowel disease affects about 2 million children and adults in the U.S. It is characterized by inflammation of the gastrointestinal lining, which causes damage and ulcerations. IBD includes Crohn's disease, which affects any part of the gastrointestinal (GI) tract, and ulcerative colitis, which is limited to the large intestine.

Researchers say childhood IBD tends to be more severe than the adult form of the disease, but until now most studies have only looked at the genes behind adult IBD.

The study, published in Nature Genetics, is the largest genetic analysis of childhood-onset inflammatory bowel disease. Researchers looked at DNA from more than 3,400 children and adolescents with IBD and compared their genetic structure to that of nearly 12,000 healthy children.

The results identified five genetic regions that increased the risk of childhood inflammatory bowel disease on chromosomes 16, 22, 10, 2, and 19.

Researchers say the most significant finding was in regard to the genetic region on chromosome 16, which is near the gene (IL27) that carries the code for a signaling protein involved in intestinal inflammation.

If further studies confirm this genetic link to childhood inflammatory bowel disease, drugs may be developed to target the gene's action and block its disease-causing actions.
By Jennifer Warner
Reviewed by Louise Chang
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