Other Types of Diabetes Mellitus back | next page 1of 1 About 15% of diabetics fall outside the typical type 1 and type 2 boundaries, including diabetes similar to type 2 diagnosed in the young, or in thin individuals. Possible causes of "other" types of diabetes include: Genetic defects in beta cell function Genetic defects in insulin action, disease of the exocrine pancreas Drug- or chemical-induced Infections Uncommon forms of immune-related diabetes, other genetic syndromes