Traditional risk factors for type 2 diabetes include older age, family history of type 2 diabetes, and overweight. Doctors can use these risk factors to estimate the chances that a patient will develop diabetes. Genetic factors are also linked to a person's risk for type 2 diabetes. However, when considered 1 at a time, these factors are not very strong predictors. Combining genetic factors might improve the ability to predict the risk for diabetes. Because genetic factors are expensive to measure, to be useful, they need to be substantially better at predicting who will develop diabetes than methods that use only traditional risk factors.