GAD2 and type 1 diabetes mellitus: GAD65 antibody epitope specificity testing showed that the frequencies of COOH-terminal epitope of the GAD65 protein (GAD65-C) Ab and GAD65-MAb were higher in the LADY and T1DM groups than in the LADA group, whereas GAD65-NAb frequency was higher in the LADA group than in the juvenile T1DM group (26).