Scientists at The Scripps Research Institute claim to have identified a genetic mutation that may be responsible for causing inflammatory bowel disease (IBD).
They said that mutation in Mbtps1 gene might contribute to IBD in humans.
"We are just beginning to get a sense of the complexity of inflammatory bowel disease as far as humans are concerned," said Bruce Beutler, M.D., who is the chair of the Scripps Research Department of Genetics.
The team led by Beutler, Research Associate Katharina Brandl, Ph.D. and former Research Associate Sophie Rutschmann showed how the gene Mbtps1 is linked to ulcerative colitis in mice.
The study revealed that crippling the protein product of the Mbtps1 gene makes mice prone to colitis.
When cells lining the lower digestive tract are stressed, they begin to synthesize a set of specific proteins to deal with the stress.
Mbtps1 and a number of other genes are needed to help process unfolded proteins by activating the unfolded protein response, but the diminished capacity of Mbtps1 causes unfolded protein to build up.
If the cells cannot deal with the excess unfolded proteins, they initiate a process called programmed cell death and quickly die.
When the cells lining the intestines die, they leave open spaces through which bacteria in the gut can invade. Ultimately what leads to the disease is not the bacteria themselves but the immune system, which creates a strong inflammatory response to the bacteria.
This response causes the bleeding, ulcers, and other symptoms that are the hallmark of IBD.