Researchers at the University of Wisconsin-Madison, including one of an Indian-origin, have identified a gene that could explain why some people are more susceptible to diabetes. The gene, found in tests on obese mice, controls tomosyn-2 and acts as a brake on insulin secretion from the pancreas. "It's too early for us to know how relevant this gene will be to human diabetes, but the concept of negative regulation is one of the most interesting things to come out of this study and that very likely applies to humans," says lead researcher Alan Attie. The researchers found tomosyn-2 while searching for genes that contribute to diabetes susceptibility in obese mice. Genetic analyses and comparisons of obese diabetes-resistant and diabetes-susceptible mouse strains revealed a single amino acid difference that destabilizes the tomosyn-2 protein in the diabetes-resistant mice, effectively releasing the brake on insulin secretion and allowing those animals to release enough insulin to avoid diabetes. Though diabetes is highly unlikely to be caused by a single gene, identifying important biological pathways can suggest clinically useful targets. "This study shows the power of genetics to discover new mechanisms for a complex disease like type 2 diabetes," concludes co-lead author Sushant Bhatnagar.