Monogenic diabetes is a specific type of diabetes caused by a mutation in a single gene, unlike type 1 and type 2 diabetes. About 80% of monogenic diabetes is misdiagnosed as type 1 or type 2 diabetes. Some types of monogenic diabetes are also different from type 1 and type 2 diabetes in terms of treatment, and some do not even require insulin or pharmacological intervention. Therefore, clarifying the diagnosis of monogenic diabetes is very important in guiding treatment. In addition, monogenic diabetes is a disease with a clear pattern of inheritance, and a clear diagnosis can provide genetic counseling for patients and their relatives, as well as guidance for having healthy babies. Monogenic diabetes should be considered if you or your family members have the following manifestations: 1. Neonatal diabetes with onset within 1 year of birth; 2. Atypical type 1 diabetes: onset within 5 years of age and negative for relevant antibodies; 3. Atypical type 2 diabetes with onset before 40 years of age and obesity is not obvious; 4. Long-term fasting hyperglycemia but normal postprandial glucose; 5. Gestational diabetes with a family history of diabetes; 6. Diabetes combined with polycystic kidney, pancreatic insufficiency and other organ malformations.