1. Department of NeurologyUniversity of Iowa Carver College of Medicine Iowa City Iowa USA
2. Neuromuscular Omnicentre (NEMO)‐Fondazione Serena Onlus Genoa Liguria Italy
3. Department of NeurosciencesRehabilitation, Ophthalmology, Genetics and Maternal/Child Sciences, University of Genova and IRCCS San Martino Genoa Italy
4. Fondazione IRCCS Istituto Neurologico Carlo Besta Milan Italy
5. University of Sydney School of Health Sciences & Children's Hospital at Westmead Sydney New South Wales Australia