TYK2 and type 2 diabetes mellitus: • TYK2 regulates apoptosis in pancreatic islet β-cells and thus may contribute to the progression of diabetes by affecting pancreatic β-cells.• Common feature genes such as DHX15, USP14, COPS3, TYK2, and RIOK2 and their co-regulatory pathways are associated with both T2DM and COVID-19.• Shows bidirectional relationship between SARS-CoV-2 infection and diabetes.