Crohn's Disease Gene Discovered

Researchers at McGill University, Canada, have discovered DNA variations in a gene that increases susceptibility to developing Crohn's Disease.

Their study was published in the January issue of the Journal Nature Genetics.

The researchers pinpointed DNA sequence variants in a gene region called NLRP3 that are associated with increased susceptibility to Crohn's Disease.

"Although the exact cause of Crohns Disease is still unknown, both environmental and genetic factors are known to play a critical role in the pathogenesis of the disease," Dr. Franchimont said.

Crohn's Disease GeneThe 400 square metres of the intestinal absorptive area is the largest single surface in or on the human body, and it is covered by billions of bacteria of the intestinal microflora living in the gastrointestinal tract.

"The single layer of cells lining your intestinal digestive tract is thus constantly exposed to high levels of bacteria and pathogens," lead reseracher, Alexandra-Chloé Villani explained.

"These cells must recognize and respond appropriately to the harmful bacteria while maintaining tolerance to the non-pathogenic 'good' (probiotic) bacteria that make up your intestinal microbial flora. This is the central challenge of the digestive immune system, which needs to balance defence versus tolerance."

"The protein encoded by the Crohn's Disease susceptibility gene NLRP3, Cryopyrin, is an intracellular bacteria sensor that plays a key role in initiating immune response," explained Villani.

Based on their results, researchers theorize the bacterial sensor Cryopyrin is probably defective in some patients, and doesn't correctly recognize the presence of harmful bacteria.