The incidence of cell death in the retina and renal tissue samples from T2DM mice, as detected by a terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay (Fig. 5K–N) and immunohistochemical (IHC) staining for activated caspase 3 (cleaved caspase 3) (Supplementary Fig. 4D–G), was significantly increased. This evidence concerns the gene CASP3 and type 2 diabetes mellitus.