GAD1 and type 1 diabetes mellitus: Comparing the frequencies of PTM GAD epitopes and PTM IA2 epitopes separately, the frequency of PTM GAD reactive T cells was significantly higher in subjects with T1D than in HLA matched controls (p=0.0069, Figure 1B) whereas the frequency of PTM IA2 reactive T cells was elevated in a few subjects but not significantly higher in subjects with T1D than in HLA matched controls (p=0.33, Figure 1C).