Nonetheless, in later stages of T2DM and in type 1 diabetes mellitus (T1DM), insulin levels markedly decline due to pancreatic damage, resulting in degenerative alterations such as reductions in pancreatic cell numbers and sizes, central region vacancies, and exhaustion of pancreatic ꞵ-cells [37,38]. The gene discussed is INS; the disease is type 1 diabetes mellitus.