In this study, we screened five marker genes that were highly related to T2DM in the lacrimal gland of db/db mice using LASSO regression, including Synm, Elovl6, Glcci1, Tnks and Ptprt. The results of multiple validation showed the model had good efficiency and stability for identifying T2DM, indicating that these five selected genes were highly correlated with T2DM and could be used as marker genes. Here, PTPRT is linked to type 2 diabetes mellitus.