Digenic Inheritance of Hepatocyte Nuclear Factor-1α and -1β With Maturity-Onset Diabetes of the Young, Polycystic Thyroid, and Urogenital Malformations
- Beate Karges, MD1,
- Carsten Bergmann, MD2,
- Katrina Scholl, MD1,
- Eberhard Heinze, MD1,
- Franz Maximilian Rasche, MD3,
- Klaus Zerres, MD2,
- Klaus-Michael Debatin, MD1,
- Martin Wabitsch, MD1 and
- Wolfram Karges, MD4
- 1Department of Pediatric Endocrinology and Diabetes, University Children's Hospital, University of Ulm, Ulm, Germany
- 2Institute for Human Genetics, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen University, Aachen, Germany
- 3Department of Nephrology, University of Ulm, Ulm, Germany
- 4Department of Endocrinology and Diabetes, RWTH Aachen University, Aachen, Germany
- Address correspondence and reprint requests to Beate Karges, MD, Department of Pediatric Endocrinology and Diabetes, University Children's Hospital, University of Ulm, Eythstrasse 24, D-89075 Ulm, Germany. E-mail: beate.karges{at}uniklinik-ulm.de
Heterozygous mutations of the POU A/homeodomain transcription factors hepatocyte nuclear factor (HNF)-1α and -1β cause maturity-onset diabetes of the young (MODY) in humans (1). HNF-1α and -1β act in a complex network of transcription factors regulating tissue-specific gene expression in the pancreas and other epithelial organs. Patients with mutations of HNF-1β (MODY5) are characterized by urogenital malformations, while extrapancreatic manifestations in patients with diabetes and HNF-1α mutations (MODY3) are not well known (2).
HISTORY AND EXAMINATION—
After an occasional blood glucose reading of 13.4 mmo/l, the diagnosis of diabetes was established in a 13-year-old girl. She was asymptomatic except for mild chronic lower abdominal discomfort. Her fasting glucose was 9.3 mmol/l, A1C was 8.5% (normal 4.2–6.1), and urine ketones were negative. After brief insulin treatment, she received 0.5 mg/day glimepiride, with a current A1C of 5.6%.
Her father (Fig. 1), diagnosed with diabetes at the age of 27 years, has received insulin since the age of 38 years. The paternal grandmother had diabetes treated with glibenclamide until she died 20 years ago, aged 62 years. Two asymptomatic sisters of the index patient were diagnosed with diabetes at the age of 14 years and 19 years. Their fasting serum glucose was 7.3 and 6.8 mmol/l, respectively, and A1C was 6.0 and 6.1%. Two hours after a 75-g oral glucose challenge, their glucose levels were 10.1 and 13.1 mmol/l, respectively. …
