An international team of scientists led by a UVA Health genomics researcher published the largest and most ancestry-diverse genetic study of type 1 diabetes ever conducted. Study findings could lead to new screening guidelines and drug therapies for type 1 diabetes.
"UVA is 1 of only 3 or 4 places in the world doing this kind of work to understand the basis of type 1 diabetes," says the study's principal investigator, Stephen S. Rich, PhD. Rich is a professor of public health sciences and founding director of UVA's Center for Public Health Genomics.
Identifying Genetic Links to Type 1 Diabetes
Rich and his team launched this study to identify genetic factors that increase the risk of type 1 diabetes. It builds on work they have been doing for decades.
In the early 2000s, Rich formed an international multicenter group called the Type 1 Diabetes Genetics Consortium to investigate the genetics of type 1 diabetes. At that time, he and his fellow researchers had identified 15 to 18 sites in the genome associated with a genetic risk of type 1 diabetes. Studies from the consortium pinpointed about 40 sites.
In the latest study, published last June in Nature Genetics, Rich and his colleagues identified 75 to over 100 sites.
"We've gone from knowing about half the genetic risk of type 1 diabetes to nearly all of the genetic risk," Rich says. "And that's very powerful, because now we can think about how to use that information to screen populations of children for type 1 diabetes risk. Those at high genetic risk could go on to have autoantibody testing to determine whether an autoimmune process is already ongoing. If it is, we can look at how far along that autoimmune process has gone and whether we can do anything about it."
Protecting Children From Diabetic Ketoacidosis
Understanding the genetics of type 1 diabetes could help protect children from a serious health emergency. In about 40% of cases, children receive a diagnosis of type 1 diabetes only after they experience diabetic ketoacidosis, a potentially life-threatening condition.
"If we identify those children who are at risk because of genetics and then screen them for the presence of 2 or more of the autoantibodies associated with type 1 diabetes, we could reduce the occurrence of diabetic ketoacidosis from about 40% to almost zero," Rich says.
Most Diverse Type 1 Diabetes Study Ever
This study included the largest-ever number of participants with non-Northern European ancestry, including those with African, Asian, and Hispanic/Latino ancestry. Overall, it enrolled 61,427 participants of all ancestries, which is about twice the size of the previous largest study.
Prior genetic studies in this field tended to exclude diverse and underserved populations. "But expanding diversity is important for two reasons," Rich says. "First, it's ethically the right thing to do. And second, studying genetically diverse populations is a more effective way to uncover unique genetic insights and identify the specific sites in the genome associated with type 1 diabetes risk."
Key Takeaways for Endocrinologists
The findings from this study could lead to the development of new genetic screening guidelines for infants and children during routine newborn blood spot screening, pediatrician office testing, or even home testing.
"Although it may not be cost-effective to do genetic screening at this time, in the future, there will be guidelines set up to provide a path for when it is appropriate to do genetic screening," Rich says. "I think within the next 5 years, endocrinologists will have guidelines about how to utilize genetic information, in whom, and at what age."
Knowing what genes are involved in type 1 diabetes could eventually lead to the discovery of type 1 diabetes therapies. "We might even be able to figure out how to intervene in the development of type 1 diabetes and perhaps delay its onset or prevent it from developing at all," Rich adds.
Future Directions for Type 1 Diabetes Research
Rich and his team are continuing to investigate the genetics of type 1 diabetes. They recently completed a study looking at the effectiveness of conducting genetic testing with saliva samples collected in pediatric waiting rooms. The study, whose findings have not yet been published, was supported through the UVA Strategic Investment Fund.
In addition, Rich and his team are starting a study in which saliva-collection tests will be sent to families at home. "We want to see if it's feasible to do testing at home, which could allow us to reach more children and do more testing on a community level," he says.
Rich hopes the findings from this study and other research will lead to more widespread screening, improved treatment, and perhaps even a cure for type 1 diabetes.