The pathogenesis of Type 2 diabetes (T2D) involves deficient insulin secretion by pancreatic β-cells, and diminished insulin effectiveness in target tissues (insulin resistance) T2D aetiology differs from that of Type 1 diabetes (T1D), in which there is absolute insulin deficiency due to the destruction of insulin-producing β-cells [14]. The gene discussed is INS; the disease is type 1 diabetes mellitus.