Il valore aggiunto della diagnostica molecolare nelle forme monogeniche di diabete mellito

Maturity Onset Diabetes of the Young (MODY), the most frequent form of monogenic diabetes, comprises a group of heterogeneous disorders, characterized by non-autoimmune diabetes due to mutations of at least 14 different genes. We report a case of a 38-years-old patient with non-autoimmune diabetes, where molecular analysis evidenced a large deletion on chromosome 17q12 including several genes, among them HNF1β associated to MODY5. The analysis allowed us to clarify the complex phenotype of the patient including, in addition to diabetes, intellectual disability, seizures, kidney cysts and facial dimorphisms. This case shows that diabetes when caused by large deletions, can be just one of the symptoms of a “clinical syndrome” that includes other features due to the deletion of neighboring genes and confirms the important role of the molecular test to obtain a correct diagnosis in a patient with a suspicion of monogenic diabetes.