A single-cell assay for transposase accessible chromatin with high-throughput sequencing showed that these effector T cells are epigenetic and have different chromatin structure induced by STAT3-GOF, CD8+T cells react with known antigen islet-specific glucose-6-phosphatase catalytic subunit-related protein, STAT3 mutations contribute to type 1 diabetes through deficiency of CD8+ T cell tolerance (39). The gene discussed is STAT3; the disease is type 1 diabetes mellitus.