Diabetic ketoacidosis (DKA) [28] and severe hypoglycaemia events (defined as a blood glucose value ≤ 3.9 mmol/L and resulting in loss of consciousness, a call for an ambulance and/or admission to hospital, or use of glucagon) in the past 6 months will also be recorded from electronic medical records to provide baseline estimates of frequency for these events. The gene discussed is GCG; the disease is Hypoglycemia.