1. Endocrine Practice Heidelberg, Molecular Genetic Laboratory, Heidelberg, Germany
2. Section of Endocrine Surgery, Department of General, Visceral and Transplantation Surgery, Medical Center, University Essen-Duisburg, Duisburg, Germany
3. Department of General and Vascular Surgery, Martin Luther University Halle-Wittenberg, Halle, Germany
4. Institute of Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany