After infecting cultured pancreatic islets with the SARS-CoV-2 virus, it was observed that the number of insulin-secretory granules in β-cells was reduced, leading to impaired glucose-dependent insulin secretion. The infection caused morphological, transcriptional, and functional changes in the β-cells of the islets, resulting in impaired glucose-stimulated insulin secretion. The gene discussed is INS; the disease is infection.