Rare forms of diabetes are defined as non-Type 1, non-Type 2 and non-gestational diabetes. It is a very heterogenous group of genetically determined diseases characterized by non-autoimmune dysfunction of the ß-cell or genetically caused insulin resistance.
The most common forms are MODY (Maturity Onset Diabetes of the Young). Molecular genetics increases our knowledge on etiology of rare forms of diabetes with important clinical consequences including disease-tailored treatment and improvement of diabetes control.