[1] Hammersmith Hosp, Dubowitz Neuromuscular Ctr, London, England
[2] Guys Hosp, Dept Paediat Neurol, London SE1 9RT, England
[3] Osped Bambino Gesu, Rome, Italy
[4] Univ Newcastle Upon Tyne, Int Ctr Life, Inst Human Genet, Newcastle Upon Tyne NE1 7RU, Tyne & Wear, England
[5] Kantonsspital Basel, Dept Anaesthesia & Res, Basel, Switzerland
[6] Robert Jones & Agnes Hunt Orthopaed Hosp, Ctr Inherited Neuromuscular Disorders, Oswestry SY10 7AG, Shrops, England