HNF4A and MODY: Although the GCK (MODY 2), HNF1A (MODY 3), and HNF4A (MODY 1) genes are responsible for the vast majority of genetic causes of MODY [6], there are other rarer MODY subtypes caused by mutations in genes not analyzed in this study, which could have been analyzed by next-generation sequencing methods [28].