The most common mutations associated with MODY occur in at least one of the following components: HNF4α (hepatocyte nuclear factor 4 alpha, MODY1), glucokinase (MODY2), HNF1α (MODY3), insulin promoter factor 1 (IPF-1, MODY4), HNF1β (MODY5) or neurogenic differentiation 1/β-cell E-box transactivator 2 (NeuroD1, BETA2, MODY6) (Fajans, Bell & Polonsky, 2001). This evidence concerns the gene HNF4A and MODY.