1 Center for Medical Genetics Ghent, Department of Dermatology, Department of Biomolecular Medicine, Ghent University Hospital, Ghent University, Ghent, Belgium.
2 Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium.
3 Department of Biomolecular Medicine, Ghent University, Ghent, Belgium.
4 Center for Medical Genetics Ghent, Department of Biomolecular Medicine, Ghent University Hospital, Ghent University, Ghent, Belgium. bert.callewaert@ugent.be.