An international team of researchers has pinpointed new genetic targets for drugs to treat Crohn’s disease, a chronic and painful condition caused by inflammation of the gastrointestinal tract.The Children’s Hospital of Philadelphia-led group used a new gene-searching method, combining a statistical tool that identifies genes interacting on the same biological pathways with highly automated gene-hunting techniques that scan the whole genome.

An initial analysis was performed on DNA from 1,758 Crohn’s patients and 1,480 people without the disease. All of them were of European ancestry. The analysis was repeated in three more groups, of both European and African ancestry.

“Among hundreds of known biological pathways, the one that surfaced from the analysis as being most significant included genes already known to be relevant to the biology of Crohn’s disease,” study leader Dr. Hakon Hakonarson, director of the Center for Applied Genomics at Children’s Hospital, said in a news release from the hospital.

The interleukin 12 (IL12) pathway governs cell receptors involved in the developed of Crohn’s disease. Previous research has found that monoclonal antibodies that block the IL12 receptor show some clinical success in treating Crohn’s disease.

The study was published online and in the March 13 print issue of The American Journal of Human Genetics.

“As we better understand the gene pathways operating in Crohn’s disease, we are uncovering more potential targets for effective drug treatments,” study co-author Dr. Robert Baldassano, a pediatric gastroenterologist and director of the Center for Pediatric Inflammatory Bowel Disease at Children’s Hospital, said in the same news release.

Developing targeted therapies based on gene pathways might enable doctors to tailor treatments to a patient’s genetic profile, he added.

(Source: Children’s Hospital of Philadelphia, news release, Feb. 26, 2009)