Changes in genes protect against hereditary intestinal diseases
Chronic bowel inflammation is partially hereditary. But there are also genetic variations that make the bearer immune. A European research network with participants from Linköping University has now found three more gene variants that protect against both Crohn’s disease and ulcerative colitis.
The results will be published in the well-known scientific journal Nature Genetics.
“Together with our earlier discoveries, this means that relatives of patients could probably be tested in the future to determine the risk of their also being stricken,” says Sven Almer, senior lecturer in gastroenterology and hepatology at Linköping University.
He is participating in a large, EU-supported study, which started just over ten years ago, aimed at mapping genetic changes behind Crohn’s disease and ulcerative colitis, widespread illnesses that affect approximately one percent of the population of the Nordic countries.
The study covers 800 families with at least two members who are ill from eleven countries. A portion of them were recruited in Linköping, Norrköping, and Jönköping. A DNA investigation of all the family members led to the discovery in 2001 of a gene called NOD2, the first gene change described in detail that turned out to lie behind a part of the heredity for Crohn’s disease. It was a groundbreaking discovery, which was also published in Nature and enjoyed great success.
Since then, more gene changes have been identified. A well-known change is found in the gene for the IL-23 (interleukin) receptor, which turned out to provide protection against intestinal diseases. With the latest DNA techniques, French and Belgian researchers have now succeeded in finding three more genetic markers there which protect equally well.
Even if the discoveries provide the opportunity for a simple blood test of people in the risk zone, Almer considers the most important advance to be increasing knowledge about the mechanisms behind the disease’s origins.
“We now understand more and more about what’s happening, how heredity combines with bacteria and an overactive immune defence,” he says.
Resequencing of positional candidates identifies low frequency IL23R coding variants protecting against inflammatory bowel disease by Yukihide Momozawa et al. Nature Genetics, Advance online publication 12 December 2010.
Sven Almer, Senior Lecturer, University Chief Physician, 010-1032179, firstname.lastname@example.org
Last updated: 2011-02-09