Researchers from the Washington University School of Medicine have found that certain viruses in the gut could make a person more likely to develop type 1 diabetes.
Professor Herbert Virgin and Dr Guoyan Zhao led the partly JDRF-funded study, which investigated the link between intestinal viruses and the development of type 1 diabetes. The team analysed the viruses that were present in monthly stool samples of 22 children under 3 years old, who all carried genes that gave them a high risk of developing the disease.
11 of the children went on to develop autoantibodies – proteins in the blood associated with type 1 – and 5 of these 11 then developed type 1 diabetes. The other 11 children did not develop autoantibodies or the condition.
The team found that children who developed type 1 diabetes had a less diverse range of viruses in their gut. They also identified one virus associated with reduced risk, and a group of viruses associated with increased risk. This suggests that the balance of these two types of viruses in the gut could affect the risk of developing type 1 diabetes.
A type of virus known as a circovirus was found in 5 of the 11 children who did not develop autoantibodies, and was not found in any of the children who did develop autoantibodies. This suggests that carriers of this circovirus are less likely to develop type 1 diabetes. By contrast, the team found that the children who had certain bacteriophages – special viruses that infect a major group of stomach bacteria – were more likely to develop autoantibodies.
The researchers have now started to look at the effects of circoviruses on the immune system and how they affect the onset of type 1 diabetes in animals. They are also aiming to produce the same findings in another group of children, to help verify the results. In the long-term, the research could be used to develop strategies to prevent type 1 diabetes by treating high-risk children with circoviruses.