There are features that make one suspect a monogenic cause for someone’s diabetes. Typical features to look for include:
• Family history of diabetes diagnosed at a young age (<30 years old)
• Individual who was diagnosed <1 year old, especially <6 months old
• Negative diabetes antibody results
• Persistently detectable C-peptide many years after diagnosis
• Chronic mildly elevated fasting blood sugars (100-140 mg/dl)
More information on typical patterns to look for can be found on our “Features to look for” page.
Who should not get genetic testing?
Genetic testing, although getting cheaper, remains an expensive test and is not indicated in most people with diabetes. Those diagnosed after 6 months of age with positive diabetes antibody testing are likely to have type 1 diabetes. Also genetic forms of diabetes usually present in early life (rarely over 30 years of age). We encourage families to talk to their doctor if they are uncertain about their antibody results.