1 Department of Dermatology, Center of Pediatric Dermatology, Erasmus MC University Medical Center Rotterdam-Sophia Children's Hospital, Rotterdam, The Netherlands.
2 Department of Dermatology, St Jansdal Hospital, Harderwijk, The Netherlands.
3 Department of Dermatology, University Medical Center Utrecht and Utrecht University, Utrecht, The Netherlands.
4 Department of Genetics, University Medical Center, University of Groningen, Groningen, The Netherlands.
5 Department of Dermatology, University Medical Center, University of Groningen, Groningen, The Netherlands.
6 Department of Genetics, University Medical Center Utrecht and Wilhelmina's Children Hospital Utrecht, Utrecht, The Netherlands.