Researchers at the Center for Public Health Genomics at the University of Virginia (Charlottesville) have developed a test that they think could predict the risk of type 1 diabetes. This would be a huge deal—preventing the situation where children are hospitalized in life-threatening diabetic ketoacidosis.
Type 1 diabetes affects 1 in 300 children and occurs as the autoimmune system destroys the immune-producing beta cells in the pancreas. The risk for type 1 diabetes is 50% genetic and 50% environmental, reports Stephen Rich, PhD, FAHA, director of the Center for Public Health Genomics. See his paper Current Opinion in Endocrinology, Diabetes, and Obesity on the role of genetics in type 1 diabetes. Rich notes that innovation in the field of genomic mapping offers a wealth of data that can be leveraged for analysis on how to improve the prediction of risk and potentially improved evaluation of treatment efficacy.
There is no single gene responsible for type 1 diabetes, which makes testing even more difficult. Rather, numerous gene variants play a role and could predict as many as 90% of the cases.
The researchers have developed an approach that involves the taking of a saliva sample, which is then checked against 82 genetic sites. “The test for high genetic risk of type 1 diabetes is based upon extensive prior research that has identified 80% to 90% of the genetic risk—that accounts for about one-half of the total risk—for type 1 diabetes” reported Rich.
Professor Rich noted in Contemporary Pediatrics, that he and the team used a cutoff to identify subjects with a 10-fold increased risk of developing type 1 diabetes. He also notes, “For those at high genetic risk, we then offer autoantibody screening—4 islet autoantibodies that are biomarkers of the potential development of type 1 diabetes. If a participant has two or more of the four autoantibodies, then we feel that careful monitoring is suggested to determine potential progression.”
Not Perfect but a Start
At a per-test cost of $7, Risk suggests that those children who are at risk—perhaps with a family history of the disease—or those deemed a higher risk can be tested periodically for the antibodies that signal active disease. At $75, the antibody test, but the genetic analysis can vet out lower-risk individuals and hence avoid unnecessary and expensive trials. Rich explains that the test “is not perfect, but a start.” The test, still in the research stage, cannot be applied commercially, and it isn’t clear yet to Rich if it can be used as a screening tool for the general population.
Rich hopes that ultimately this test “can be a first-line indication of who would be at high genetic risk of type 1 diabetes—or better define an individual’s genetic risk—that could lead to targeted immune testing.” Rich continued “Although there is only the autoantibody test that predicts stage of risk, research is ongoing by many groups that can identify more and better biomarkers as we know more about the development of type 1 diabetes from multiple sources. The genetics is a one-time test, and can form the baseline of all subsequent tests for improved prediction, prevention, and discovery of new therapeutics.”
Stephen Rich, PhD, FAHA, director of the Center for Public Health Genomics