1 Department of Dermatology, Allergology and Venereology, Helsinki University Hospital and University of Helsinki, Helsinki, Finland.
2 Société Française Des Sciences Humaines Sur la Peau (SFSHP), Société Française de Dermatologie, Paris, France.
3 MAGEC Reference Centre for Rare Genetic Skin Diseases and Paediatric Dermatology Unit, Department of Paediatrics, University Hospital Dijon-Bourgogne, Dijon, France.