How to Screen Appropriately for Monogenic Diabetes

The causation of diabetes in a given individual may be heterogeneous but is broadly categorized into insulin-mediated diabetes (type 1 diabetes) and non-insulin mediated diabetes (type 2 diabetes). The falling cost of genetic characterization using a gene panel approach decreases the need to define the genetic etiology prior to testing. The factors that discriminated monogenic diabetes from type 1 diabetes were an older age at diagnosis, better glycemic control, female sex and a parent with diabetes. HNF1A is a transcription factor necessary for pancreatic islet development and functioning. The clinical features of affected patients overlap significantly with those affected by HNF1A mutations and are characterized by progressive β-cell dysfunction which is responsive to sulfonylurea treatment. The commonest causes of monogenic diabetes encountered in clinical practice are those caused by mutations in GCK, HNF1A, and HNF4A.