Finding might someday lead to targeted treatment, researchers say
Scientists have identified a gene variant present in some people of white European descent who have type 2 diabetes.
Although it’s not yet clear how the gene works, it may prove a future target for treatments, among other benefits, say the authors of a study published March 2 in the Journal of the American Medical Association.
As with so many gene studies, however, these findings aren’t likely to translate into anything clinically meaningful soon.
“This shows an association between this gene and an increased risk of diabetes compared to the general population,” said Dr. Steven D. Wittlin, clinical director of the endocrine-metabolism division and director of the Diabetes Service at the University of Rochester Medical Center.
“If we can find out how this gene is associated with diabetes from a pathophysiological point of view, then we can figure out how to intervene, but that’s a lot of ifs, and right now we have 92.5 percent of people with diabetes who don’t have this gene,” said Wittlin, who was not involved in the study.
Between 7 and 8 percent of the patients involved in this study had the gene variant, the researchers found.
Some 250 million people around the world have type 2 diabetes, a disorder in which glucose is not properly metabolized in the body.
The main risk factors for type 2 diabetes are age, being overweight or obese, and family history. Native Americans, blacks and Hispanics also have a higher prevalence of the disease than whites.
Several diabetes-related genes have already been identified, although all of these together account for only 10 to 15 percent of type 2 diabetes cases, an accompanying editorial pointed out.
For this study, investigators at the University of Catanzaro in Italy looked at people with and without diabetes in three populations: about 6,500 Italian patients; close to 2,000 U.S. residents; and about 400 French people.
Among the study participants with type 2 diabetes, about 7 to 8 percent of people in each group had the variant of the HMGA1 gene. In the Italian group, this represented a 16-fold higher risk in people with type 2 diabetes versus the control group.
The gene appears to be involved in insulin resistance, a hallmark of diabetes.
But the presence of the gene in people without diabetes varied immensely (from 0.43 to 4.7 percent), making its effect hard to determine, said the editorial.
Although the experts believe the gene may one day help predict individuals likely to develop diabetes, Wittlin is more circumspect, given the relatively small proportion of people who have the variant.
“In the best of circumstances that are reported in this study, 7.7 percent of patients with type 2 diabetes have this gene variant,” he said. “Certainly one can identify patients at risk for type 2 more on the basis of such things as family history or body build.”
Another problem with the study is that it was conducted only in white Europeans so “the applicability to other ethnicities is totally unknown,” said Wittlin.
Further study of the gene’s effect on insulin resistance in other racial groups is needed, the authors noted.
Tags: DNA, Gene, Health, Scientists