1. Institute of Human Genetics, University Medical Center Hamburg-Eppendorf , 20246 Hamburg , Germany
2. Institute of Biochemistry and Molecular Biology II, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine University , 40225 Düsseldorf , Germany
3. Institute of Clinical Chemistry and Laboratory Medicine, Section Mass Spectrometry and Proteomics, University Medical Center Hamburg-Eppendorf , 20246 Hamburg , Germany
4. Department of Dermatology and Venereology, University Medical Center Hamburg-Eppendorf , 20246 Hamburg , Germany