Type 1 (juvenile) diabetes and celiac disease appear to share a common genetic origin, scientists at the University of Cambridge and Barts and The London School of Medicine and Dentistry, have confirmed.

Their findings, which are reported in this week’s edition of the New England Journal of Medicine, identified seven chromosome regions which are shared between the two diseases. The research suggests that type 1 diabetes and celiac disease may be caused by common underlying mechanisms such as autoimmunity-related tissue damage and intolerance to dietary antigens (foreign substances which prompt an immune response).

Type 1 diabetes is an autoimmune disorder which causes the body to attack the beta cells of the pancreas, limiting its ability to produce the insulin necessary to regulate blood sugar levels. Celiac disease, also an autoimmune disorder, attacks the small intestine and is triggered by the consumption of gluten (a protein found in wheat, barley and rye) and cereals. The development and anatomy of the small intestine and pancreas are closely related, and the gut immune system shares connections with pancreatic lymph nodes, which have been linked to an inflammation of the pancreas and the destruction of beta cells.

In order to assess the genetic similarities and differences between the two inflammatory disorders, the researchers obtained 9339 control samples, 8064 samples from people with type 1 diabetes and 2560 samples from individuals with celiac disease. They found a total of seven loci (regions of a chromosome) were shared between the two.

The researchers, who were funded by the Juvenile Diabetes Research Foundation, the Wellcome Trust and Coeliac UK, believe that these regions of the chromosomes regulate the mechanisms that cause the body’s own immune system to attack both the beta cells in the pancreas and the small intestine. Their results suggest that type 1 diabetes and celiac disease not only share genetic causes but could have similar environmental triggers as well.

Professor John Todd, from the University of Cambridge, said: “The next step is to understand how these susceptibility genes affect the immune system, and to keep exploring environmental factors that might alter the risk of type 1 diabetes, which results from an incredibly complex interaction between nature and nurture.”

Professor David van Heel, from Barts and The London School of Medicine and Dentistry , said: “These findings suggest common mechanisms causing both coeliac and type 1 diabetes - we did not expect to see this very high degree of shared genetic risk factors.”

Richard A. Insel, MD., Executive Vice President, Research, at JDRF, said: “These studies demonstrate that type 1 diabetes and celiac disease share far greater genetic overlap than had been appreciated, which helps explain the high prevalence of both diseases occurring simultaneously in an individual, and provide new avenues for understanding the cause and mechanisms of both diseases.”

Sarah Sleet, Chief Executive of Coeliac UK said: “This is a real advancement in understanding the underlying mechanisms generating celiac disease, a much under diagnosed condition which affects 1 in 100 people in the UK today however, only 1 in 8 of those has currently been diagnosed. We hope that these findings will help in increased awareness and diagnostic understanding of both celiac disease and type 1 diabetes.”

Type 1 diabetes and celiac disease together affect about 1% of the population.

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For additional information please contact:
Genevieve Maul, Office of Communications, University of Cambridge
Tel: +44 (0) 1223 332300, +44 (0) 1223 765542
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Notes to Editors:

1. The article ‘Shared and Distinct Genetic Variants in Type 1 Diabetes and Celiac Disease’ will appear in the online edition of the New England Journal of Medicine on December 10 (and in the 25 December 2008 issue of the Journal).

2. About type 1 diabetes

  * Type 1 diabetes is a serious, life threatening condition caused by the body’s own immune system destroying insulin producing cells in the pancreas.
  * Insulin is vital because it converts glucose from food into energy and a lack of insulin quickly results in serious illness and, if untreated, death.
  * Type 1 diabetes strikes suddenly and without warning, usually in childhood and remains for life.
  * Multiple daily insulin injections and blood tests are essential just to stay alive but are not a cure and can not prevent the long term, potentially devastating complications including blindness, limb amputations, kidney failure, heart disease and strokes.
  * Every year around £2.5 billion is spent in the UK on treating type 1 diabetes and its complications.

3. University of Cambridge:
As the University of Cambridge approaches its eight-hundredth anniversary in 2009, it is looking to the future. Its mission is to contribute to society through the pursuit of education, learning and research at the highest international levels of excellence. It admits the very best and brightest students, regardless of background, and offers one of the UK’s most generous bursary schemes.

Contact: Genevieve Maul
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44-012-233-32300
University of Cambridge