Furthermore, in a study involving 922 families referred for MODY testing, spontaneous de novo mutations affecting GCK, HNF1A, or HNF4A genes were reported in 11 of the 150 individuals who did not have autosomal dominant inheritance of diabetes mellitus or a multigenerational family history of hyperglycemia [19]. The gene discussed is HNF1A; the disease is Hyperglycemia.