1 Center for Genetic Medicine Research, Children's Research Institute, Children's National Hospital, Washington, DC, USA.
2 Department of Genomics and Precision Medicine, George Washington University School of Medicine and Health Sciences, Washington, DC, USA.
3 School of Pharmacy and Pharmaceutical Sciences, Binghamton University, Binghamton, NY, USA.
4 The Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health, London, UK.
5 National Institute for Health Research, Great Ormond Street Institute of Child Health Biomedical Research Centre, University College London, London, UK.