As a result, we could subtype T1D patients into four groups based on anti-GAD Ab (< 1.5 U/ml, negative; ≧ 1.5 U/ml, positive) and IgE (< 170 U/ml, low; ≧ 170 U/ml, high) profile (Fig. 2). Here, GAD1 is linked to type 1 diabetes mellitus.