What Causes Type 1 Diabetes?

No one knows for sure what causes type 1 diabetes, but scientists think it has something to do with genes. Genes are like instructions for how the body should look and work that are passed on by parents to their kids. But just getting the genes for diabetes isn't usually enough. In most cases, something else has to happen — like getting a virus infection — for a person to get type 1 diabetes.
Type 1 diabetes can't be prevented. Doctors can't even tell who will get it and who won't.