[1] UCL Great Ormond St Inst Child Hlth, Dubowitz Neuromuscular Ctr, London, England
[2] Univ Portsmouth, Sch Pharm & Biomed Sci, Portsmouth, Hants, England
[3] Newcastle Univ, Inst Med Genet, John Walton Muscular Dystrophy Res Ctr, Newcastle Upon Tyne, Tyne & Wear, England
[4] Inst Myol, Serv Clin Res & Databases, Paris, France
[5] Radboud Univ Nijmegen Med Ctr, Nijmegen, Netherlands
[6] Leiden Univ, Med Ctr, Dept Neurol, Leiden, Netherlands
[7] Newcastle Upon Tyne Hosp NHS Fdn Trust, Northern Genet Serv, Inst Human Genet, Int Ctr Life, Newcastle Upon Tyne, Tyne & Wear, England
[8] UCL Great Ormond St Inst Child Hlth, NIHR Great Ormond St Hosp, Biomed Res Ctr, London, England