1. Department of Child Neurology, Hospital Sant Joan de Déu, University of Barcelona, Barcelona, Spain
2. Department of Child Neurology, Hospital General de Granollers, Barcelona, Spain
3. Clinical Biochemistry, Hospital Sant Joan de Déu, University of Barcelona, Barcelona, Spain
4. Centre for the Biomedical Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain
5. Division of Inborn Errors of Metabolism-IBC, Department of Biochemistry and Molecular Genetics, Hospital Clinic, Barcelona, Spain
6. Departamento de Biología Molecular, Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), Centro de Biología Molecular Severo Ochoa CSIC-UAM, IDIPAZ, Universidad Autónoma de Madrid, Madrid, Spain