Gluten-free bread may be off the menu for coeliacs

TCD researchers are tracking down the genes involved in coeliac disease, writes BETH O'DONOGHUE

THE RESTRICTIVE diets endured by sufferers of coeliac disease may one day be a thing of the past.

Dublin scientists are investigating the role of specific genes in the development of coeliac disease, as part of worldwide research that will ultimately lead to better methods for diagnosis and treatment of the condition.

Coeliac disease is caused by the body’s inappropriate reaction to gluten, a protein found in wheat, oats and other cereal crops.

“Coeliac disease is an inherited disease, partly caused by inheritable factors, part due to diet, [so] we know that coeliacs will have certain shared genetic characteristics that are different to healthy populations,” says Dr Ross McManus, senior lecturer in molecular medicine and head of the genomics research team at Trinity College Dublin.

Previous research by the team identified genes involved in causing susceptibility to the disease. This was done by comparing genomes, a person’s entire genetic information. They matched up coeliac patients against the genomes of healthy individuals.

“So far, it’s been very productive work, over 25-30 genes of interest have been identified that are different in terms of coeliacs versus non-coeliacs,” says McManus.

“Most are in regions that are associated with the immune system. This supports the view that with coeliac disease the immune system is not functioning properly.”

The genomics research group at TCD is now investigating how differences within the particular genes highlighted cause susceptibility to the disease, according to McManus. These single differences in a gene’s DNA sequence are known as single-nucleotide polymorphisms (SNPs).

Under normal circumstances, a gene provides the recipe for making a protein. “These genetic differences seen in [coeliacs] might be doing lots of different things. They might mean that the structure of the protein produced is altered or that the gene is turned on for too long or too short a period of time,” he says.

Science Foundation Ireland awarded funding in excess of €1 million to the team in April this year, under its Private Investigators scheme.

The team’s findings will give an insight into the mechanics of coeliac disease but also a broader view of the general mechanics of a range of inflammatory diseases that are associated with malfunctions of the immune system, such as rheumatoid arthritis and type 1 diabetes.

“The big hope is that we’ll find it’s not just one disease but many diseases that are affected by the same gene regions. There are undoubtedly relationships between inflammatory diseases. If we know more about one, chances are we will gain insight into the others,” says McManus.

In order to find out more about these links, the researchers at TCD are participating in an immunochip microarray study involving thousands of participants worldwide.

The researchers are using one tiny microchip to check each patient’s genome for SNPs associated with 25 inflammatory diseases, including coeliac disease.

This will enable researchers to find particular SNPs that are common to all or many of the diseases, according to McManus.

“If we could find common features to these [inflammatory] diseases, we could find the best targets to treat the diseases.”

This provides hope for coeliac sufferers everywhere that in the future gluten-free bread will be nothing more than a distasteful memory.