Race and Type 1 Diabetes
Unlike type 2 diabetes, type 1 is much more heavily influenced by genetic factors, and some ethnic groups are at higher risk than others. In the United States, whites are more likely to develop type 1 (in which the body’s immune system attacks the cells that make the hormone insulin) than African-Americans or Latinos.
Globally, the differences are even more dramatic: In China, for example, type 1 diabetes rates are 10 to 20 times lower than in Europe, Australia, and North America. Meanwhile, tiny Finland’s rates of type 1 diabetes are the highest in the world: 60 out of every 100,000 people—almost triple the U.S. average.
The huge differences are a strong clue that the genetic makeup of different ethnic groups plays a role in the rate of type 1. The explanation, researchers think, can be found in a complex set of genes called HLA. There are thousands of different HLA variants. Some ethnic groups, it turns out, have HLA genes that protect them from type 1, while others have HLA combinations that increase the risk.
That doesn’t mean the environment can be ignored, however: Breast-feeding, childhood infections, and the foods you eat as an infant have been studied as triggers that may kick off the autoimmune attack on insulin-producing cells in people predisposed to type 1 because of gene variants. But scientists don’t know for sure.
There’s also an inherited component: People with type 1 family members—a parent or sibling, for instance—have a greater risk for the disease. The research team behind Type 1 Diabetes TrialNet is using this connection to learn about type 1 and research ways to prevent it. They screen family members of people with type 1 for early stages of the disease and enroll interested and eligible family members in studies that focus on type 1 prevention. You can learn more at trialnet.org.