1. Department of General Internal Medicine, Endocrinology and Metabolic Diseases Leiden University Medical Center PO Box 9600, 2300 RC Leiden, the Netherlands.
2. TNO-Metabolic Health Research, Gaubius Laboratory, PO Box 2215, 2333 CK Leiden, the Netherlands.
3. Department of Human Genetics Leiden University Medical Center PO Box 9600, 2300 RC Leiden, the Netherlands.
4. Department of Cardiology Leiden University Medical Center PO Box 9600, 2300 RC Leiden, the Netherlands.