It is less common in Western countries and more common in Eastern countries, especially in Japan.[5] The peak onset of this condition is between 60 and 69 years of age.[6] It is the third leading cause of hypoglycemia in Japan after insulinoma and extra-pancreatic neoplasm.[7] However, IAS is difficult to diagnose in patients with new-onset hypoglycemia because it is usually obscured by causes such as sepsis, alcohol intoxication, malnutrition, insulin, and drug overdose. The gene discussed is INS; the disease is Hypoglycemia.