As elevated glucagon levels in the fasted state contribute to hyperglycemia in patients with T2D [49], we next tested if selected candidate genes that exhibit decreased DNA methylation and increased expression in pancreatic islets of T2D compared with non-diabetic donors contribute to increased glucagon secretion in pancreatic α-cells (αTC1-6 cells). The gene discussed is GCG; the disease is type 2 diabetes mellitus.