In order to assess whether the deletion or mutation of the Tyk2 gene leads to reduced expression of the Tyk2 gene and reduced protective capability dependent on IFN against EMC-D virus-induced diabetes, we evaluated the expression levels of the Tyk2 gene, Jak1 gene and ISGs in pancreatic β-cells, splenocytes and embryonic fibroblasts (mEFs) with IFN treatment. Here, TYK2 is linked to diabetes mellitus.