GAD1 and type 1 diabetes mellitus: Literature searches were conducted in the database of PubMed Central and the Japan Medical Abstracts Society (Ichushi-Web) with keywords such as “pregnancy”, “gestational diabetes”, “diagnostic criteria”, “immune tolerance”, “regulatory T cells”, “genetics”, “type 1 diabetes”, “fulminant type 1 diabetes”, “slowly progressive type 1 diabetes”, “latent autoimmune diabetes in adults”, “GAD autoantibodies”, and “prediction”.