1. Department of Neurology; St.Olavs Hospital; Trondheim University Hospital; Trondheim Norway
2. Centre for Pediatric and Adolescence Medicine; University of Heidelberg; Heidelberg Germany
3. Department of Neurology; Oslo University Hospital; Oslo Norway
4. Institute of Clinical Medicine; University of Oslo; Oslo Norway
5. Department of Medical Genetics; Oslo University Hospital; Oslo Norway
6. Norwegian National Unit for Newborn Screening at Division of Pediatric and Adolescent Medicine; Oslo University Hospital; Oslo Norway
7. Department of Pathology; Oslo University Hospital; Oslo Norway
8. Department of Neurology; Drammen Hospital; Vestre Viken Hospital Trust; Drammen Norway