GCG and insulin-resistant diabetes mellitus: Patient 1 is a 55-year-old woman referred for early-onset insulin-resistant diabetes mellitus, diagnosed at 26, initially treated with metformin, glucagon-like peptide 1 analogs, followed by insulin (continuous subcutaneous insulin infusion, daily insulin requirement 2 UI/kg/day with HbA1c = 7.3% (56 mmol/mol)).