Conclusion Since the patients have the clinical characteristics of maternal transmission, hearing loss and impaired insulin secretion, we conclude that maternally inherited diabetes and deafness ( MIDD) is a new diabetes subtype associated with a single mitochondrial mutation. 结论由于这类病人具有母系遗传、耳聋、进行性胰岛素分泌不全等特征,临床上可将这一类型的糠尿病分为一种新亚型-MIDD。