Type 1 diabetes is characterized primarily by insulin deficiency, whereas type 2 diabetes is characterized primarily by insulin resistance with relative insulin deficiency.6–11 The lack of insulin reservoir in type 1 diabetes often results in greater glycemic excursion, which may present as extremely high and low glucose levels.1 Indeed, we found that subjects with type 1 diabetes had greater average MAGE, higher AUC of nocturnal high glucose, and higher AUC of nocturnal low glucose. This evidence concerns the gene INS and type 1 diabetes mellitus.