In the current study, we initially designed and performed in vivo experiments with non-diabetic control, ZnT8-KO, STZ-induced (animal model for T1DM) and ZnT8-KO-STZ mice and then with db/db (animal model for T2DM) and ZnT8-KO-db/db mice. This evidence concerns the gene SLC30A8 and type 1 diabetes mellitus.