[Maturity-onset diabetes of the young (MODY): the history of its dismemberment].

Type 2 diabetes (T2D) is a complex multifactorial disease. Genetic susceptibility is clearly needed, but in most cases, is not sufficient to induce T2D. Environmental factors are determinant in most patients to develop T2D. Monogenic forms of diabetes such as the maturity-onset diabetes of the young (MODY) represent a model to study the genetic basis of T2D. Studies in MODY individuals and families lead to a genetic definition of MODY subtypes with profound implications for our understanding of gene mutations involved in the development of T2D through our understanding on the major role of these genes and on their transcriptional activity on b-cell development and function; and on the regulation of glucose and insulin metabolism. Our current knowledge on the heterogeneity of MODY diabetes and contribution to our comprehension of the molecular mechanisms involved in T2D are described.