We perfomed mutational analyses of the major MODY genes (HNF1A, HNF4A, HNF1B, GCK) on 263 Japanese patients with early-onset, nonobese, MODY-like diabetes mellitus referred to Osaka City General Hospital for diagnosis. Mutations were identified in 103 (35.9%) patients; 57 mutations in GCK; 29, HNF1A; 7, HNF4A; and 10, HNF1B. Compared with these mutation-positive patients, 160 mutation-negative patients were significantly older (P=0.003), and had higher BMI percentile at diagnosis (P=0.0006). Biparental diabetes was found only in mutation-negative patients, and interestingly, when patients with single affected parents were compared, maternal inheritance of diabetes was significantly more common in mutation-negative patients (P=0.0332). These results suggest that mutation-negative patients have clinical characteristics in common with early-onset type 2 diabetes, and non-Mendelian inheritance should be considered at least for part of these patients.
27 - 29 Sep 2018
European Society for Paediatric Endocrinology